diff --git a/Libraries/SPTarkov.Server.Core/Controllers/QuestController.cs b/Libraries/SPTarkov.Server.Core/Controllers/QuestController.cs
index 5a57183d..28e3dcf3 100644
--- a/Libraries/SPTarkov.Server.Core/Controllers/QuestController.cs
+++ b/Libraries/SPTarkov.Server.Core/Controllers/QuestController.cs
@@ -209,7 +209,7 @@ public class QuestController(
     )
     {
         var quest = questHelper.GetQuestFromDb(request.QuestId, pmcData);
-        List<string> handoverQuestTypes = ["HandoverItem", "WeaponAssembly"];
+        HashSet<string> handoverQuestTypes = ["HandoverItem", "WeaponAssembly"];
         var output = eventOutputHolder.GetOutput(sessionID);
 
         var isItemHandoverQuest = true;
diff --git a/Libraries/SPTarkov.Server.Core/Generators/BotEquipmentModGenerator.cs b/Libraries/SPTarkov.Server.Core/Generators/BotEquipmentModGenerator.cs
index aa742b3e..d1cd9fa3 100644
--- a/Libraries/SPTarkov.Server.Core/Generators/BotEquipmentModGenerator.cs
+++ b/Libraries/SPTarkov.Server.Core/Generators/BotEquipmentModGenerator.cs
@@ -197,7 +197,8 @@ public class BotEquipmentModGenerator(
                 );
                 switch (plateSlotFilteringOutcome.Result)
                 {
-                    case Result.UNKNOWN_FAILURE or Result.NO_DEFAULT_FILTER:
+                    case Result.UNKNOWN_FAILURE
+                    or Result.NO_DEFAULT_FILTER:
                         if (logger.IsLogEnabled(LogLevel.Debug))
                         {
                             logger.Debug(
@@ -844,8 +845,8 @@ public class BotEquipmentModGenerator(
 
         return item.Properties.Slots is null
             || !item.Properties.Slots.Any()
-                && item.Properties.Cartridges?.Count == 0
-                && item.Properties.Chambers?.Count == 0;
+                && !item.Properties.Cartridges.Any()
+                && !item.Properties.Chambers.Any();
     }
 
     /// <summary>
@@ -1342,7 +1343,7 @@ public class BotEquipmentModGenerator(
 
         // Filter modpool to only items that appear in parents allowed list
         preFilteredModPool = preFilteredModPool
-            .Where(tpl => parentSlot.Props.Filters[0].Filter.Contains(tpl))
+            .Where(tpl => parentSlot.Props.Filters.First().Filter.Contains(tpl))
             .ToHashSet();
         if (preFilteredModPool.Count == 0)
         {
@@ -1554,7 +1555,8 @@ public class BotEquipmentModGenerator(
                     StringComparison.Ordinal
                 )
             )
-            ?.Props.Filters?[0].Filter;
+            ?.Props.Filters?.First()
+            .Filter;
 
         // Mod isn't in existing pool, only add if it has no children and exists inside parent filter
         if (
@@ -1721,7 +1723,7 @@ public class BotEquipmentModGenerator(
     )
     {
         // Find compatible mods and make an array of them
-        var allowedItems = parentSlot.Props.Filters[0].Filter;
+        var allowedItems = parentSlot.Props.Filters.First().Filter;
 
         // Find mod item that fits slot from sorted mod array
         var exhaustableModPool = CreateExhaustableArray(allowedItems);
@@ -1964,9 +1966,9 @@ public class BotEquipmentModGenerator(
             modPool[cylinderMagTemplate.Id] = new Dictionary<string, HashSet<MongoId>>();
             foreach (var camora in camoraSlots)
             {
-                modPool[cylinderMagTemplate.Id][camora.Name] = camora.Props.Filters?[
-                    0
-                ].Filter.ToHashSet();
+                modPool[cylinderMagTemplate.Id][camora.Name] = camora
+                    .Props.Filters.First()
+                    .Filter.ToHashSet();
             }
 
             itemModPool = modPool[cylinderMagTemplate.Id];
diff --git a/Libraries/SPTarkov.Server.Core/Generators/BotWeaponGenerator.cs b/Libraries/SPTarkov.Server.Core/Generators/BotWeaponGenerator.cs
index 784b748a..0bbb4a8a 100644
--- a/Libraries/SPTarkov.Server.Core/Generators/BotWeaponGenerator.cs
+++ b/Libraries/SPTarkov.Server.Core/Generators/BotWeaponGenerator.cs
@@ -228,7 +228,7 @@ public class BotWeaponGenerator(
 
         // Add cartridge(s) to gun chamber(s)
         if (
-            weaponItemTemplate.Properties?.Chambers?.Count > 0
+            (weaponItemTemplate.Properties?.Chambers).Any()
             && weaponItemTemplate
                 .Properties.Chambers.FirstOrDefault()
                 .Props.Filters.FirstOrDefault()
@@ -768,7 +768,8 @@ public class BotWeaponGenerator(
 
         var cartridges = weaponTemplate
             .Properties?.Chambers?.FirstOrDefault()
-            ?.Props?.Filters?[0].Filter;
+            ?.Props?.Filters?.First()
+            .Filter;
         if (cartridges is not null)
         {
             return cartridges;
@@ -845,7 +846,10 @@ public class BotWeaponGenerator(
         if (!string.IsNullOrEmpty(weaponTemplate.Properties.LinkedWeapon))
         {
             var ammoInChamber = itemHelper.GetItem(
-                weaponTemplate.Properties.Chambers[0].Props.Filters[0].Filter.FirstOrDefault()
+                weaponTemplate
+                    .Properties.Chambers.First()
+                    .Props.Filters.First()
+                    .Filter.FirstOrDefault()
             );
             return !ammoInChamber.Key ? null : ammoInChamber.Value.Properties.Caliber;
         }
diff --git a/Libraries/SPTarkov.Server.Core/Generators/FenceBaseAssortGenerator.cs b/Libraries/SPTarkov.Server.Core/Generators/FenceBaseAssortGenerator.cs
index 802c274d..6765a127 100644
--- a/Libraries/SPTarkov.Server.Core/Generators/FenceBaseAssortGenerator.cs
+++ b/Libraries/SPTarkov.Server.Core/Generators/FenceBaseAssortGenerator.cs
@@ -236,8 +236,8 @@ public class FenceBaseAssortGenerator(
         {
             // Get the cartridge tpl found inside ammo box
             var cartridgeTplInBox = rootItemDb
-                .Properties.StackSlots[0]
-                .Props.Filters[0]
+                .Properties.StackSlots.First()
+                .Props.Filters.First()
                 .Filter.FirstOrDefault();
 
             // Look up cartridge tpl in db
@@ -288,9 +288,9 @@ public class FenceBaseAssortGenerator(
             foreach (var requiredSlot in requiredSlots)
             {
                 var modItemDbDetails = itemHelper
-                    .GetItem(requiredSlot.Props.Filters[0].Plate.Value)
+                    .GetItem(requiredSlot.Props.Filters.First().Plate.Value)
                     .Value;
-                var plateTpl = requiredSlot.Props.Filters[0].Plate; // `Plate` property appears to be the 'default' item for slot
+                var plateTpl = requiredSlot.Props.Filters.First().Plate; // `Plate` property appears to be the 'default' item for slot
                 if (plateTpl is null || plateTpl.Value.IsEmpty())
                 // Some bsg plate properties are empty, skip mod
                 {
@@ -325,7 +325,7 @@ public class FenceBaseAssortGenerator(
         {
             foreach (var plateSlot in plateSlots)
             {
-                var plateTpl = plateSlot.Props.Filters[0].Plate;
+                var plateTpl = plateSlot.Props.Filters.First().Plate;
                 if (string.IsNullOrEmpty(plateTpl))
                 // Bsg data lacks a default plate, skip adding mod
                 {
@@ -337,7 +337,7 @@ public class FenceBaseAssortGenerator(
                     new Item
                     {
                         Id = new MongoId(),
-                        Template = plateSlot.Props.Filters[0].Plate.Value, // `Plate` property appears to be the 'default' item for slot
+                        Template = plateSlot.Props.Filters.First().Plate.Value, // `Plate` property appears to be the 'default' item for slot
                         ParentId = armor[0].Id,
                         SlotId = plateSlot.Name,
                         Upd = new Upd
diff --git a/Libraries/SPTarkov.Server.Core/Generators/WeaponGen/Implementations/ExternalInventoryMagGen.cs b/Libraries/SPTarkov.Server.Core/Generators/WeaponGen/Implementations/ExternalInventoryMagGen.cs
index 3eedc338..58f10c52 100644
--- a/Libraries/SPTarkov.Server.Core/Generators/WeaponGen/Implementations/ExternalInventoryMagGen.cs
+++ b/Libraries/SPTarkov.Server.Core/Generators/WeaponGen/Implementations/ExternalInventoryMagGen.cs
@@ -190,7 +190,7 @@ public class ExternalInventoryMagGen(
 
         // All possible mags that fit into the weapon excluding blacklisted
         var magazinePool = magSlot
-            .Props.Filters[0]
+            .Props.Filters.First()
             .Filter.Where(x => !magazineBlacklist.Contains(x))
             .Select(x => itemHelper.GetItem(x).Value);
         if (magazinePool is null)
diff --git a/Libraries/SPTarkov.Server.Core/Helpers/BotGeneratorHelper.cs b/Libraries/SPTarkov.Server.Core/Helpers/BotGeneratorHelper.cs
index f07b4f94..fe2cd7a1 100644
--- a/Libraries/SPTarkov.Server.Core/Helpers/BotGeneratorHelper.cs
+++ b/Libraries/SPTarkov.Server.Core/Helpers/BotGeneratorHelper.cs
@@ -758,7 +758,7 @@ public class BotGeneratorHelper(
         var excludedFilter = propFilters?.FirstOrDefault()?.ExcludedFilter ?? [];
         var filter = propFilters?.FirstOrDefault()?.Filter ?? [];
 
-        if (propFilters?.Count == 0)
+        if (!propFilters.Any())
         // no filters, item is fine to add
         {
             return true;
diff --git a/Libraries/SPTarkov.Server.Core/Helpers/BotWeaponGeneratorHelper.cs b/Libraries/SPTarkov.Server.Core/Helpers/BotWeaponGeneratorHelper.cs
index 8a3124db..5d73f035 100644
--- a/Libraries/SPTarkov.Server.Core/Helpers/BotWeaponGeneratorHelper.cs
+++ b/Libraries/SPTarkov.Server.Core/Helpers/BotWeaponGeneratorHelper.cs
@@ -37,7 +37,7 @@ public class BotWeaponGeneratorHelper(
             var firstSlotAmmoTpl =
                 magTemplate
                     .Properties.Cartridges.FirstOrDefault()
-                    ?.Props.Filters[0]
+                    ?.Props.Filters.First()
                     .Filter.FirstOrDefault() ?? new MongoId(null);
             var ammoMaxStackSize =
                 itemHelper.GetItem(firstSlotAmmoTpl).Value?.Properties?.StackMaxSize ?? 1;
@@ -53,7 +53,7 @@ public class BotWeaponGeneratorHelper(
         }
         else
         {
-            chamberBulletCount = magTemplate.Properties.Cartridges?[0].MaxCount;
+            chamberBulletCount = magTemplate.Properties.Cartridges?.First().MaxCount;
         }
 
         // Get the amount of bullets that would fit in the internal magazine
diff --git a/Libraries/SPTarkov.Server.Core/Helpers/ItemHelper.cs b/Libraries/SPTarkov.Server.Core/Helpers/ItemHelper.cs
index f1a2de5b..7170823f 100644
--- a/Libraries/SPTarkov.Server.Core/Helpers/ItemHelper.cs
+++ b/Libraries/SPTarkov.Server.Core/Helpers/ItemHelper.cs
@@ -1387,10 +1387,10 @@ public class ItemHelper(
     /// <param name="ammoBoxDetails">Item template from items db</param>
     public void AddCartridgesToAmmoBox(List<Item> ammoBox, TemplateItem ammoBoxDetails)
     {
-        var ammoBoxMaxCartridgeCount = ammoBoxDetails.Properties.StackSlots[0].MaxCount;
+        var ammoBoxMaxCartridgeCount = ammoBoxDetails.Properties.StackSlots.First().MaxCount;
         var cartridgeTpl = ammoBoxDetails
-            .Properties.StackSlots[0]
-            .Props.Filters[0]
+            .Properties.StackSlots.First()
+            .Props.Filters.First()
             .Filter.FirstOrDefault();
         var cartridgeDetails = GetItem(cartridgeTpl);
         var cartridgeMaxStackSize = cartridgeDetails.Value.Properties.StackMaxSize;
@@ -1440,10 +1440,11 @@ public class ItemHelper(
     /// <param name="ammoBoxDetails">Item template from items db</param>
     public void AddSingleStackCartridgesToAmmoBox(List<Item> ammoBox, TemplateItem ammoBoxDetails)
     {
-        var ammoBoxMaxCartridgeCount = ammoBoxDetails.Properties?.StackSlots?[0].MaxCount ?? 0;
-        var cartridgeTpl = ammoBoxDetails.Properties?.StackSlots?[0].Props?.Filters?[
-            0
-        ].Filter?.FirstOrDefault();
+        var ammoBoxMaxCartridgeCount = ammoBoxDetails.Properties?.StackSlots?.First().MaxCount ?? 0;
+        var cartridgeTpl = ammoBoxDetails
+            .Properties?.StackSlots?.First()
+            .Props?.Filters?.First()
+            .Filter?.FirstOrDefault();
         ammoBox.Add(
             CreateCartridges(ammoBox[0].Id, cartridgeTpl.Value, (int)ammoBoxMaxCartridgeCount, 0)
         );
@@ -1610,7 +1611,7 @@ public class ItemHelper(
     /// <returns>Tpl of cartridge</returns>
     protected string? GetRandomValidCaliber(TemplateItem magTemplate)
     {
-        var ammoTpls = magTemplate.Properties.Cartridges[0].Props.Filters[0].Filter;
+        var ammoTpls = magTemplate.Properties.Cartridges.First().Props.Filters.First().Filter;
         var calibers = ammoTpls
             .Where(x => GetItem(x).Key)
             .Select(x => GetItem(x).Value.Properties.Caliber)
diff --git a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Globals.cs b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Globals.cs
index 711107e5..62449acb 100644
--- a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Globals.cs
+++ b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Globals.cs
@@ -18,10 +18,10 @@ public record Globals
     public LocationInfection LocationInfection { get; set; }
 
     [JsonPropertyName("bot_presets")]
-    public List<BotPreset> BotPresets { get; set; }
+    public IEnumerable<BotPreset> BotPresets { get; set; }
 
     [JsonPropertyName("BotWeaponScatterings")]
-    public List<BotWeaponScattering> BotWeaponScatterings { get; set; }
+    public IEnumerable<BotWeaponScattering> BotWeaponScatterings { get; set; }
 
     [JsonPropertyName("ItemPresets")]
     public Dictionary<MongoId, Preset> ItemPresets { get; set; }
@@ -48,7 +48,7 @@ public record PlayerSettings
     public double MinStepSoundVolumeMultiplier { get; set; }
 
     [JsonPropertyName("MovementRolloffMultipliers")]
-    public List<MovementRolloffMultiplier> MovementRolloffMultipliers { get; set; }
+    public IEnumerable<MovementRolloffMultiplier> MovementRolloffMultipliers { get; set; }
 
     [JsonPropertyName("OutdoorRolloffMult")]
     public double OutdoorRolloffMultiplier { get; set; }
@@ -88,7 +88,7 @@ public record RadioBroadcastSettings
     public bool EnabledBroadcast { get; set; }
 
     [JsonPropertyName("RadioStations")]
-    public List<RadioStation> RadioStations { get; set; }
+    public IEnumerable<RadioStation> RadioStations { get; set; }
 }
 
 public record RadioStation
@@ -181,10 +181,10 @@ public record ArtilleryMapSettings
     public double InitCalledShellingTime { get; set; }
 
     [JsonPropertyName("ShellingZones")]
-    public List<ShellingZone> ShellingZones { get; set; }
+    public IEnumerable<ShellingZone> ShellingZones { get; set; }
 
     [JsonPropertyName("Brigades")]
-    public List<Brigade> Brigades { get; set; }
+    public IEnumerable<Brigade> Brigades { get; set; }
 
     [JsonPropertyName("ArtilleryShellingAirDropSettings")]
     public ArtilleryShellingAirDropSettings ArtilleryShellingAirDropSettings { get; set; }
@@ -235,7 +235,7 @@ public record ShellingZone
     public XYZ ExplosionDistanceRange { get; set; }
 
     [JsonPropertyName("AlarmStages")]
-    public List<AlarmStage> AlarmStages { get; set; }
+    public IEnumerable<AlarmStage> AlarmStages { get; set; }
 
     [JsonPropertyName("BeforeShellingSignalTime")]
     public double BeforeShellingSignalTime { get; set; }
@@ -268,7 +268,7 @@ public record Brigade
     public double Id { get; set; }
 
     [JsonPropertyName("ArtilleryGuns")]
-    public List<ArtilleryGun> ArtilleryGuns { get; set; }
+    public IEnumerable<ArtilleryGun> ArtilleryGuns { get; set; }
 }
 
 public record ArtilleryGun
@@ -1329,7 +1329,7 @@ public record Exp
     public Level Level { get; set; }
 
     [JsonPropertyName("loot_attempts")]
-    public List<LootAttempt> LootAttempts { get; set; }
+    public IEnumerable<LootAttempt> LootAttempts { get; set; }
 
     // Confirmed in client
     [JsonPropertyName("expForLevelOneDogtag")]
@@ -1408,7 +1408,7 @@ public record MatchEnd
     public double TransitExperienceReward { get; set; }
 
     [JsonPropertyName("transit_mult")]
-    public List<Dictionary<string, double>> TransitMultiplier { get; set; }
+    public IEnumerable<Dictionary<string, double>> TransitMultiplier { get; set; }
 }
 
 public record Kill
@@ -1507,7 +1507,7 @@ public record Armor
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("class")]
-    public List<Class> Classes { get; set; }
+    public IEnumerable<Class> Classes { get; set; }
 }
 
 public record Class
@@ -1529,7 +1529,7 @@ public record Mastering
     public string Name { get; set; }
 
     [JsonPropertyName("Templates")]
-    public List<MongoId> Templates { get; set; }
+    public IEnumerable<MongoId> Templates { get; set; }
 
     [JsonPropertyName("Progress")]
     public double Progress { get; set; }
@@ -1558,7 +1558,7 @@ public record Customization
     public Dictionary<string, WildFeet> Feet { get; set; }
 
     [JsonPropertyName("CustomizationVoice")]
-    public List<CustomizationVoice> VoiceOptions { get; set; }
+    public IEnumerable<CustomizationVoice> VoiceOptions { get; set; }
 
     [JsonPropertyName("BodyParts")]
     public BodyParts BodyParts { get; set; }
@@ -2281,7 +2281,7 @@ public record Stimulator
 
     public double BuffLoopTime { get; set; }
 
-    public Dictionary<string, List<Buff>> Buffs { get; set; }
+    public Dictionary<string, IEnumerable<Buff>> Buffs { get; set; }
 }
 
 public record Buff
@@ -2762,7 +2762,7 @@ public record RagFair
     public float RenewPricePerHour { get; set; }
 
     [JsonPropertyName("maxActiveOfferCount")]
-    public List<MaxActiveOfferCount> MaxActiveOfferCount { get; set; }
+    public IEnumerable<MaxActiveOfferCount> MaxActiveOfferCount { get; set; }
 
     [JsonPropertyName("balancerRemovePriceCoefficient")]
     public float BalancerRemovePriceCoefficient { get; set; }
@@ -2810,7 +2810,7 @@ public record RagFair
     public double ChangePriceCoef { get; set; }
 
     [JsonPropertyName("ItemRestrictions")]
-    public List<ItemGlobalRestrictions> ItemRestrictions { get; set; }
+    public IEnumerable<ItemGlobalRestrictions> ItemRestrictions { get; set; }
 
     [JsonPropertyName("balancerUserItemSaleCooldownEnabled")]
     public bool BalancerUserItemSaleCooldownEnabled { get; set; }
@@ -3117,7 +3117,7 @@ public record RequirementReferences
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("Alpinist")]
-    public List<Alpinist> Alpinists { get; set; }
+    public IEnumerable<Alpinist> Alpinists { get; set; }
 }
 
 public record Alpinist
@@ -3398,7 +3398,7 @@ public record BtrMapConfig
     public string MapID { get; set; }
 
     [JsonPropertyName("pathsConfigurations")]
-    public List<PathConfig> PathsConfigurations { get; set; }
+    public IEnumerable<PathConfig> PathsConfigurations { get; set; }
 }
 
 public record PathConfig
@@ -3542,7 +3542,7 @@ public record SkillsSettings
     public WeaponSkills Revolver { get; set; }
 
     [JsonPropertyName("SMG")]
-    public List<object> SMG { get; set; }
+    public IEnumerable<object> SMG { get; set; }
 
     [JsonPropertyName("Assault")]
     public WeaponSkills Assault { get; set; }
@@ -3554,16 +3554,16 @@ public record SkillsSettings
     public WeaponSkills Sniper { get; set; }
 
     [JsonPropertyName("LMG")]
-    public List<object> LMG { get; set; }
+    public IEnumerable<object> LMG { get; set; }
 
     [JsonPropertyName("HMG")]
-    public List<object> HMG { get; set; }
+    public IEnumerable<object> HMG { get; set; }
 
     [JsonPropertyName("Launcher")]
-    public List<object> Launcher { get; set; }
+    public IEnumerable<object> Launcher { get; set; }
 
     [JsonPropertyName("AttachedLauncher")]
-    public List<object> AttachedLauncher { get; set; }
+    public IEnumerable<object> AttachedLauncher { get; set; }
 
     [JsonPropertyName("Melee")]
     public MeleeSkill Melee { get; set; }
@@ -3572,58 +3572,58 @@ public record SkillsSettings
     public WeaponSkills DMR { get; set; }
 
     [JsonPropertyName("BearAssaultoperations")]
-    public List<object> BearAssaultoperations { get; set; }
+    public IEnumerable<object> BearAssaultoperations { get; set; }
 
     [JsonPropertyName("BearAuthority")]
-    public List<object> BearAuthority { get; set; }
+    public IEnumerable<object> BearAuthority { get; set; }
 
     [JsonPropertyName("BearAksystems")]
-    public List<object> BearAksystems { get; set; }
+    public IEnumerable<object> BearAksystems { get; set; }
 
     [JsonPropertyName("BearHeavycaliber")]
-    public List<object> BearHeavycaliber { get; set; }
+    public IEnumerable<object> BearHeavycaliber { get; set; }
 
     [JsonPropertyName("BearRawpower")]
-    public List<object> BearRawpower { get; set; }
+    public IEnumerable<object> BearRawpower { get; set; }
 
     [JsonPropertyName("BipodErgonomicsBonusPerLevel")]
     public double BipodErgonomicsBonusPerLevel { get; set; }
 
     [JsonPropertyName("UsecArsystems")]
-    public List<object> UsecArsystems { get; set; }
+    public IEnumerable<object> UsecArsystems { get; set; }
 
     [JsonPropertyName("UsecDeepweaponmodding_Settings")]
-    public List<object> UsecDeepweaponmodding_Settings { get; set; }
+    public IEnumerable<object> UsecDeepweaponmodding_Settings { get; set; }
 
     [JsonPropertyName("UsecLongrangeoptics_Settings")]
-    public List<object> UsecLongrangeoptics_Settings { get; set; }
+    public IEnumerable<object> UsecLongrangeoptics_Settings { get; set; }
 
     [JsonPropertyName("UsecNegotiations")]
-    public List<object> UsecNegotiations { get; set; }
+    public IEnumerable<object> UsecNegotiations { get; set; }
 
     [JsonPropertyName("UsecTactics")]
-    public List<object> UsecTactics { get; set; }
+    public IEnumerable<object> UsecTactics { get; set; }
 
     [JsonPropertyName("BotReload")]
-    public List<object> BotReload { get; set; }
+    public IEnumerable<object> BotReload { get; set; }
 
     [JsonPropertyName("CovertMovement")]
     public CovertMovement CovertMovement { get; set; }
 
     [JsonPropertyName("FieldMedicine")]
-    public List<object> FieldMedicine { get; set; }
+    public IEnumerable<object> FieldMedicine { get; set; }
 
     [JsonPropertyName("Search")]
     public Search Search { get; set; }
 
     [JsonPropertyName("Sniping")]
-    public List<object> Sniping { get; set; }
+    public IEnumerable<object> Sniping { get; set; }
 
     [JsonPropertyName("ProneMovement")]
-    public List<object> ProneMovement { get; set; }
+    public IEnumerable<object> ProneMovement { get; set; }
 
     [JsonPropertyName("FirstAid")]
-    public List<object> FirstAid { get; set; }
+    public IEnumerable<object> FirstAid { get; set; }
 
     [JsonPropertyName("LightVests")]
     public ArmorSkills LightVests { get; set; }
@@ -3632,19 +3632,19 @@ public record SkillsSettings
     public ArmorSkills HeavyVests { get; set; }
 
     [JsonPropertyName("WeaponModding")]
-    public List<object> WeaponModding { get; set; }
+    public IEnumerable<object> WeaponModding { get; set; }
 
     [JsonPropertyName("AdvancedModding")]
-    public List<object> AdvancedModding { get; set; }
+    public IEnumerable<object> AdvancedModding { get; set; }
 
     [JsonPropertyName("NightOps")]
-    public List<object> NightOps { get; set; }
+    public IEnumerable<object> NightOps { get; set; }
 
     [JsonPropertyName("SilentOps")]
-    public List<object> SilentOps { get; set; }
+    public IEnumerable<object> SilentOps { get; set; }
 
     [JsonPropertyName("Lockpicking")]
-    public List<object> Lockpicking { get; set; }
+    public IEnumerable<object> Lockpicking { get; set; }
 
     [JsonPropertyName("WeaponTreatment")]
     public WeaponTreatment WeaponTreatment { get; set; }
@@ -3653,22 +3653,22 @@ public record SkillsSettings
     public MagDrills MagDrills { get; set; }
 
     [JsonPropertyName("Freetrading")]
-    public List<object> Freetrading { get; set; }
+    public IEnumerable<object> Freetrading { get; set; }
 
     [JsonPropertyName("Auctions")]
-    public List<object> Auctions { get; set; }
+    public IEnumerable<object> Auctions { get; set; }
 
     [JsonPropertyName("Cleanoperations")]
-    public List<object> Cleanoperations { get; set; }
+    public IEnumerable<object> Cleanoperations { get; set; }
 
     [JsonPropertyName("Barter")]
-    public List<object> Barter { get; set; }
+    public IEnumerable<object> Barter { get; set; }
 
     [JsonPropertyName("Shadowconnections")]
-    public List<object> Shadowconnections { get; set; }
+    public IEnumerable<object> Shadowconnections { get; set; }
 
     [JsonPropertyName("Taskperformance")]
-    public List<object> Taskperformance { get; set; }
+    public IEnumerable<object> Taskperformance { get; set; }
 
     [JsonPropertyName("Perception")]
     public Perception Perception { get; set; }
@@ -3692,7 +3692,7 @@ public record SkillsSettings
     public AimDrills AimDrills { get; set; }
 
     [JsonPropertyName("BotSound")]
-    public List<object> BotSound { get; set; }
+    public IEnumerable<object> BotSound { get; set; }
 
     [JsonPropertyName("TroubleShooting")]
     public TroubleShooting TroubleShooting { get; set; }
@@ -3823,7 +3823,7 @@ public record Crafting
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("DependentSkillRatios")]
-    public List<DependentSkillRatio> DependentSkillRatios { get; set; }
+    public IEnumerable<DependentSkillRatio> DependentSkillRatios { get; set; }
 
     [JsonPropertyName("PointsPerCraftingCycle")]
     public double PointsPerCraftingCycle { get; set; }
@@ -3908,7 +3908,7 @@ public record Endurance
     public double GainPerFatigueStack { get; set; }
 
     [JsonPropertyName("DependentSkillRatios")]
-    public List<DependentSkillRatio> DependentSkillRatios { get; set; }
+    public IEnumerable<DependentSkillRatio> DependentSkillRatios { get; set; }
 
     [JsonPropertyName("QTELevelMultipliers")]
     public Dictionary<string, Dictionary<string, double>> QTELevelMultipliers { get; set; }
@@ -3920,7 +3920,7 @@ public record Strength
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("DependentSkillRatios")]
-    public List<DependentSkillRatio> DependentSkillRatios { get; set; }
+    public IEnumerable<DependentSkillRatio> DependentSkillRatios { get; set; }
 
     [JsonPropertyName("SprintActionMin")]
     public double SprintActionMin { get; set; }
@@ -3941,7 +3941,7 @@ public record Strength
     public double PushUpMax { get; set; }
 
     [JsonPropertyName("QTELevelMultipliers")]
-    public List<QTELevelMultiplier> QTELevelMultipliers { get; set; }
+    public IEnumerable<QTELevelMultiplier> QTELevelMultipliers { get; set; }
 
     [JsonPropertyName("FistfightAction")]
     public double FistfightAction { get; set; }
@@ -4088,7 +4088,7 @@ public record WeaponTreatment
     public double SkillPointsPerRepair { get; set; }
 
     [JsonPropertyName("Filter")]
-    public List<object> Filter { get; set; }
+    public IEnumerable<object> Filter { get; set; }
 
     [JsonPropertyName("WearAmountRepairGunsReducePerLevel")]
     public double WearAmountRepairGunsReducePerLevel { get; set; }
@@ -4151,7 +4151,7 @@ public record Perception
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("DependentSkillRatios")]
-    public List<SkillRatio> DependentSkillRatios { get; set; }
+    public IEnumerable<SkillRatio> DependentSkillRatios { get; set; }
 
     [JsonPropertyName("OnlineAction")]
     public double OnlineAction { get; set; }
diff --git a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Quest.cs b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Quest.cs
index 20f42673..20b603e5 100644
--- a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Quest.cs
+++ b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Quest.cs
@@ -361,25 +361,25 @@ public record QuestConditionCounterCondition
     public object? Value { get; set; }
 
     [JsonPropertyName("weapon")]
-    public List<string>? Weapon { get; set; }
+    public HashSet<string>? Weapon { get; set; }
 
     [JsonPropertyName("distance")]
     public CounterConditionDistance? Distance { get; set; }
 
     [JsonPropertyName("equipmentInclusive")]
-    public List<List<string>>? EquipmentInclusive { get; set; }
+    public IEnumerable<List<string>>? EquipmentInclusive { get; set; }
 
     [JsonPropertyName("weaponModsInclusive")]
-    public List<List<string>>? WeaponModsInclusive { get; set; }
+    public IEnumerable<List<string>>? WeaponModsInclusive { get; set; }
 
     [JsonPropertyName("weaponModsExclusive")]
-    public List<List<string>>? WeaponModsExclusive { get; set; }
+    public IEnumerable<List<string>>? WeaponModsExclusive { get; set; }
 
     [JsonPropertyName("enemyEquipmentInclusive")]
-    public List<List<string>>? EnemyEquipmentInclusive { get; set; }
+    public IEnumerable<List<string>>? EnemyEquipmentInclusive { get; set; }
 
     [JsonPropertyName("enemyEquipmentExclusive")]
-    public List<List<string>>? EnemyEquipmentExclusive { get; set; }
+    public IEnumerable<List<string>>? EnemyEquipmentExclusive { get; set; }
 
     [JsonPropertyName("weaponCaliber")]
     public List<string>? WeaponCaliber { get; set; }
diff --git a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Reward.cs b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Reward.cs
index 0f7c32f1..aec7a18b 100644
--- a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Reward.cs
+++ b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/Reward.cs
@@ -49,7 +49,7 @@ public record Reward
     public bool? FindInRaid { get; set; }
 
     [JsonPropertyName("gameMode")]
-    public List<string>? GameMode { get; set; }
+    public IEnumerable<string>? GameMode { get; set; }
 
     /// <summary>
     ///     Game editions whitelisted to get reward
diff --git a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/TemplateItem.cs b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/TemplateItem.cs
index 4f327362..dba88ffd 100644
--- a/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/TemplateItem.cs
+++ b/Libraries/SPTarkov.Server.Core/Models/Eft/Common/Tables/TemplateItem.cs
@@ -88,7 +88,7 @@ public record Props
     private string? _unlootableFromSlot;
 
     [JsonPropertyName("AllowSpawnOnLocations")]
-    public List<string>? AllowSpawnOnLocations { get; set; }
+    public IEnumerable<string>? AllowSpawnOnLocations { get; set; }
 
     [JsonPropertyName("BeltMagazineRefreshCount")]
     public double? BeltMagazineRefreshCount { get; set; }
@@ -257,7 +257,7 @@ public record Props
     public int? ExtraSizeUp { get; set; }
 
     [JsonPropertyName("FlareTypes")]
-    public List<string>? FlareTypes { get; set; }
+    public IEnumerable<string>? FlareTypes { get; set; }
 
     [JsonPropertyName("ExtraSizeDown")]
     public int? ExtraSizeDown { get; set; }
@@ -313,7 +313,7 @@ public record Props
     }
 
     [JsonPropertyName("UnlootableFromSide")]
-    public List<PlayerSideMask>? UnlootableFromSide { get; set; }
+    public IEnumerable<PlayerSideMask>? UnlootableFromSide { get; set; }
 
     // Type confirmed via client
     [JsonPropertyName("AnimationVariantsNumber")]
@@ -362,10 +362,10 @@ public record Props
     public bool? CanPutIntoDuringTheRaid { get; set; }
 
     [JsonPropertyName("CantRemoveFromSlotsDuringRaid")]
-    public List<EquipmentSlots>? CantRemoveFromSlotsDuringRaid { get; set; }
+    public IEnumerable<EquipmentSlots>? CantRemoveFromSlotsDuringRaid { get; set; }
 
     [JsonPropertyName("KeyIds")]
-    public List<string>? KeyIds { get; set; }
+    public IEnumerable<string>? KeyIds { get; set; }
 
     [JsonPropertyName("TagColor")]
     public double? TagColor { get; set; }
@@ -464,7 +464,7 @@ public record Props
     public double? SightModesCount { get; set; }
 
     [JsonPropertyName("OpticCalibrationDistances")]
-    public List<double>? OpticCalibrationDistances { get; set; }
+    public IEnumerable<double>? OpticCalibrationDistances { get; set; }
 
     [JsonPropertyName("ScopesCount")]
     public double? ScopesCount { get; set; }
@@ -473,10 +473,10 @@ public record Props
     public object? AimSensitivity { get; set; } // TODO: object here
 
     [JsonPropertyName("Zooms")]
-    public List<List<double>>? Zooms { get; set; }
+    public IEnumerable<List<double>>? Zooms { get; set; }
 
     [JsonPropertyName("CalibrationDistances")]
-    public List<List<double>>? CalibrationDistances { get; set; }
+    public IEnumerable<List<double>>? CalibrationDistances { get; set; }
 
     [JsonPropertyName("Intensity")]
     public double? Intensity { get; set; }
@@ -560,7 +560,7 @@ public record Props
     public double? MagAnimationIndex { get; set; }
 
     [JsonPropertyName("Cartridges")]
-    public List<Slot>? Cartridges { get; set; }
+    public IEnumerable<Slot>? Cartridges { get; set; }
 
     [JsonPropertyName("CanFast")]
     public bool? CanFast { get; set; }
@@ -630,10 +630,10 @@ public record Props
     public double? ContainerSpawnChanceModifier { get; set; }
 
     [JsonPropertyName("SpawnFilter")]
-    public List<object>? SpawnFilter { get; set; } // TODO: object here
+    public IEnumerable<object>? SpawnFilter { get; set; } // TODO: object here
 
     [JsonPropertyName("containType")]
-    public List<object>? ContainType { get; set; } // TODO: object here
+    public IEnumerable<object>? ContainType { get; set; } // TODO: object here
 
     [JsonPropertyName("sizeWidth")]
     public double? SizeWidth { get; set; }
@@ -648,7 +648,7 @@ public record Props
     public string? SpawnTypes { get; set; }
 
     [JsonPropertyName("lootFilter")]
-    public List<object>? LootFilter { get; set; } // TODO: object here
+    public IEnumerable<object>? LootFilter { get; set; } // TODO: object here
 
     [JsonPropertyName("spawnRarity")]
     public string? SpawnRarity { get; set; }
@@ -660,7 +660,7 @@ public record Props
     public double? MaxCountSpawn { get; set; }
 
     [JsonPropertyName("openedByKeyID")]
-    public List<string>? OpenedByKeyID { get; set; }
+    public IEnumerable<string>? OpenedByKeyID { get; set; }
 
     [JsonPropertyName("RigLayoutName")]
     public string? RigLayoutName { get; set; }
@@ -669,7 +669,7 @@ public record Props
     public double? MaxDurability { get; set; }
 
     [JsonPropertyName("armorZone")]
-    public List<string>? ArmorZone { get; set; }
+    public IEnumerable<string>? ArmorZone { get; set; }
 
     // Type confirmed via client
     [JsonPropertyName("armorClass")]
@@ -677,10 +677,10 @@ public record Props
     public int? ArmorClass { get; set; }
 
     [JsonPropertyName("armorColliders")]
-    public List<string>? ArmorColliders { get; set; }
+    public IEnumerable<string>? ArmorColliders { get; set; }
 
     [JsonPropertyName("armorPlateColliders")]
-    public List<string>? ArmorPlateColliders { get; set; }
+    public IEnumerable<string>? ArmorPlateColliders { get; set; }
 
     [JsonPropertyName("bluntDamageReduceFromSoftArmor")]
     public bool? BluntDamageReduceFromSoftArmor { get; set; }
@@ -801,7 +801,7 @@ public record Props
     public double? shotgunDispersion { get; set; }
 
     [JsonPropertyName("Chambers")]
-    public List<Slot>? Chambers { get; set; }
+    public IEnumerable<Slot>? Chambers { get; set; }
 
     [JsonPropertyName("CameraSnap")]
     public double? CameraSnap { get; set; }
@@ -835,7 +835,7 @@ public record Props
     public XYZ? RotationCenterNoStock { get; set; }
 
     [JsonPropertyName("ShotsGroupSettings")]
-    public List<ShotsGroupSettings>? ShotsGroupSettings { get; set; }
+    public IEnumerable<ShotsGroupSettings>? ShotsGroupSettings { get; set; }
 
     [JsonPropertyName("FoldedSlot")]
     public string? FoldedSlot { get; set; }
@@ -1226,7 +1226,7 @@ public record Props
 
     // Confirmed on client - MongoId
     [JsonPropertyName("TargetItemFilter")]
-    public List<MongoId>? TargetItemFilter { get; set; }
+    public IEnumerable<MongoId>? TargetItemFilter { get; set; }
 
     [JsonPropertyName("RepairQuality")]
     public double? RepairQuality { get; set; }
@@ -1434,7 +1434,7 @@ public record Props
     public double? MalfFeedChance { get; set; }
 
     [JsonPropertyName("StackSlots")]
-    public List<StackSlot>? StackSlots { get; set; }
+    public IEnumerable<StackSlot>? StackSlots { get; set; }
 
     [JsonPropertyName("type")]
     public string? Type { get; set; }
@@ -1497,7 +1497,7 @@ public record Props
     public bool? RemoveShellAfterFire { get; set; }
 
     [JsonPropertyName("RepairStrategyTypes")]
-    public List<RepairStrategyType>? RepairStrategyTypes { get; set; }
+    public IEnumerable<RepairStrategyType>? RepairStrategyTypes { get; set; }
 
     [JsonPropertyName("IsEncoded")]
     public bool? IsEncoded { get; set; }
@@ -1539,10 +1539,10 @@ public record Props
     public bool? AvailableAsDefault { get; set; }
 
     [JsonPropertyName("ProfileVersions")]
-    public List<string>? ProfileVersions { get; set; }
+    public IEnumerable<string>? ProfileVersions { get; set; }
 
     [JsonPropertyName("Side")]
-    public List<string>? Side { get; set; }
+    public IEnumerable<string>? Side { get; set; }
 
     [JsonPropertyName("BipodCameraSnapMultiplier")]
     public double? BipodCameraSnapMultiplier { get; set; }
@@ -1578,7 +1578,7 @@ public record WeaponRecoilSettings
     public bool? Enable { get; set; }
 
     [JsonPropertyName("Values")]
-    public List<WeaponRecoilSettingValues>? Values { get; set; }
+    public IEnumerable<WeaponRecoilSettingValues>? Values { get; set; }
 }
 
 public record WeaponRecoilSettingValues
@@ -1623,7 +1623,7 @@ public record WeaponRecoilTransformationCurve
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("Keys")]
-    public List<WeaponRecoilTransformationCurveKey>? Keys { get; set; }
+    public IEnumerable<WeaponRecoilTransformationCurveKey>? Keys { get; set; }
 }
 
 public record WeaponRecoilTransformationCurveKey
@@ -1695,7 +1695,7 @@ public record GridProps
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("filters")]
-    public List<GridFilter>? Filters { get; set; }
+    public IEnumerable<GridFilter>? Filters { get; set; }
 
     [JsonPropertyName("cellsH")]
     public int? CellsH { get; set; }
@@ -1779,7 +1779,7 @@ public record SlotProps
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("filters")]
-    public List<SlotFilter>? Filters { get; set; }
+    public IEnumerable<SlotFilter>? Filters { get; set; }
 
     [JsonPropertyName("MaxStackCount")]
     public double? MaxStackCount { get; set; }
@@ -1800,10 +1800,10 @@ public record SlotFilter
     public MongoId? Plate { get; set; }
 
     [JsonPropertyName("armorColliders")]
-    public List<string>? ArmorColliders { get; set; }
+    public IEnumerable<string>? ArmorColliders { get; set; }
 
     [JsonPropertyName("armorPlateColliders")]
-    public List<string>? ArmorPlateColliders { get; set; }
+    public IEnumerable<string>? ArmorPlateColliders { get; set; }
 
     [JsonPropertyName("Filter")]
     public HashSet<MongoId>? Filter { get; set; }
@@ -1851,7 +1851,7 @@ public record StackSlotProps
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("filters")]
-    public List<SlotFilter>? Filters { get; set; }
+    public IEnumerable<SlotFilter>? Filters { get; set; }
 }
 
 public record RandomLootSettings
@@ -1866,13 +1866,13 @@ public record RandomLootSettings
     public bool? AllowToSpawnQuestItems { get; set; }
 
     [JsonPropertyName("countByRarity")]
-    public List<object>? CountByRarity { get; set; } // TODO: object here
+    public IEnumerable<object>? CountByRarity { get; set; } // TODO: object here
 
     [JsonPropertyName("excluded")]
     public RandomLootExcluded? Excluded { get; set; }
 
     [JsonPropertyName("filters")]
-    public List<object>? Filters { get; set; } // TODO: object here
+    public IEnumerable<object>? Filters { get; set; } // TODO: object here
 
     [JsonPropertyName("findInRaid")]
     public bool? FindInRaid { get; set; }
@@ -1890,13 +1890,13 @@ public record RandomLootExcluded
     public Dictionary<string, object>? ExtensionData { get; set; }
 
     [JsonPropertyName("categoryTemplates")]
-    public List<object>? CategoryTemplates { get; set; } // TODO: object here
+    public IEnumerable<object>? CategoryTemplates { get; set; } // TODO: object here
 
     [JsonPropertyName("rarity")]
-    public List<string>? Rarity { get; set; }
+    public IEnumerable<string>? Rarity { get; set; }
 
     [JsonPropertyName("templates")]
-    public List<object>? Templates { get; set; } // TODO: object here
+    public IEnumerable<object>? Templates { get; set; } // TODO: object here
 }
 
 public record EffectsHealth
diff --git a/Libraries/SPTarkov.Server.Core/Models/Eft/Match/EndLocalRaidRequestData.cs b/Libraries/SPTarkov.Server.Core/Models/Eft/Match/EndLocalRaidRequestData.cs
index d2592651..5269405f 100644
--- a/Libraries/SPTarkov.Server.Core/Models/Eft/Match/EndLocalRaidRequestData.cs
+++ b/Libraries/SPTarkov.Server.Core/Models/Eft/Match/EndLocalRaidRequestData.cs
@@ -25,7 +25,7 @@ public record EndLocalRaidRequestData : IRequestData
     ///     Insured items left in raid by player
     /// </summary>
     [JsonPropertyName("lostInsuredItems")]
-    public List<Item>? LostInsuredItems { get; set; }
+    public IEnumerable<Item>? LostInsuredItems { get; set; }
 
     /// <summary>
     ///     Items sent via traders to player, keyed to service e.g. BTRTransferStash
diff --git a/Libraries/SPTarkov.Server.Core/Services/FenceService.cs b/Libraries/SPTarkov.Server.Core/Services/FenceService.cs
index b17cef34..90917fa5 100644
--- a/Libraries/SPTarkov.Server.Core/Services/FenceService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/FenceService.cs
@@ -1282,14 +1282,14 @@ public class FenceService(
         foreach (var requiredSlot in softInsertSlots)
         {
             var modItemDbDetails = itemHelper
-                .GetItem(requiredSlot.Props.Filters[0].Plate.Value)
+                .GetItem(requiredSlot.Props.Filters.First().Plate.Value)
                 .Value;
 
             var durabilityValues = GetRandomisedArmorDurabilityValues(
                 modItemDbDetails,
                 traderConfig.Fence.ArmorMaxDurabilityPercentMinMax
             );
-            var plateTpl = requiredSlot.Props.Filters[0].Plate ?? string.Empty; // "Plate" property appears to be the 'default' item for slot
+            var plateTpl = requiredSlot.Props.Filters.First().Plate ?? string.Empty; // "Plate" property appears to be the 'default' item for slot
             if (plateTpl.IsEmpty())
             // Some bsg plate properties are empty, skip mod
             {
@@ -1348,7 +1348,7 @@ public class FenceService(
     {
         foreach (var plateSlot in plateSlots)
         {
-            var plateTpl = plateSlot.Props.Filters[0].Plate;
+            var plateTpl = plateSlot.Props.Filters.First().Plate;
             if (plateTpl == null || plateTpl.Value.IsEmpty())
             // Bsg data lacks a default plate, skip randomising for this mod
             {
diff --git a/Libraries/SPTarkov.Server.Core/Services/InsuranceService.cs b/Libraries/SPTarkov.Server.Core/Services/InsuranceService.cs
index 3378c663..2fac8c27 100644
--- a/Libraries/SPTarkov.Server.Core/Services/InsuranceService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/InsuranceService.cs
@@ -251,7 +251,7 @@ public class InsuranceService(
     /// <returns>InsuranceEquipmentPkg list</returns>
     public List<InsuranceEquipmentPkg> MapInsuredItemsToTrader(
         MongoId sessionId,
-        List<Item> lostInsuredItems,
+        IEnumerable<Item> lostInsuredItems,
         PmcData pmcProfile
     )
     {
diff --git a/Libraries/SPTarkov.Server.Core/Services/LocationLifecycleService.cs b/Libraries/SPTarkov.Server.Core/Services/LocationLifecycleService.cs
index 0198689d..7ee27d25 100644
--- a/Libraries/SPTarkov.Server.Core/Services/LocationLifecycleService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/LocationLifecycleService.cs
@@ -1168,7 +1168,7 @@ public class LocationLifecycleService(
         string locationName
     )
     {
-        if (request.LostInsuredItems?.Count > 0)
+        if (request.LostInsuredItems is not null && request.LostInsuredItems.Any())
         {
             var mappedItems = insuranceService.MapInsuredItemsToTrader(
                 sessionId,
diff --git a/Libraries/SPTarkov.Server.Core/Services/Mod/CustomItemService.cs b/Libraries/SPTarkov.Server.Core/Services/Mod/CustomItemService.cs
index 3411d6f5..4c6091b0 100644
--- a/Libraries/SPTarkov.Server.Core/Services/Mod/CustomItemService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/Mod/CustomItemService.cs
@@ -299,7 +299,7 @@ public class CustomItemService(
             var wall = itemHelper.GetItem(wallId);
             if (wall.Key)
             {
-                wall.Value.Properties.Grids.First().Props.Filters[0].Filter.Add(newItemId);
+                wall.Value.Properties.Grids.First().Props.Filters.First().Filter.Add(newItemId);
             }
         }
     }
@@ -328,7 +328,7 @@ public class CustomItemService(
         var weaponSlots = weapon.Value.Properties.Slots;
         foreach (var slot in weaponSlots)
         {
-            baseWeaponModObject[slot.Name] = [.. slot.Props.Filters[0].Filter];
+            baseWeaponModObject[slot.Name] = [.. slot.Props.Filters.First().Filter];
         }
 
         // Get PMCs
diff --git a/Libraries/SPTarkov.Server.Core/Services/RagfairLinkedItemService.cs b/Libraries/SPTarkov.Server.Core/Services/RagfairLinkedItemService.cs
index 5afbb763..9568b25e 100644
--- a/Libraries/SPTarkov.Server.Core/Services/RagfairLinkedItemService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/RagfairLinkedItemService.cs
@@ -130,7 +130,7 @@ public class RagfairLinkedItemService(
 
         // Get the first cylinder filter tpl
         var cylinderTpl =
-            cylinderMod.Props?.Filters?[0].Filter?.FirstOrDefault() ?? new MongoId(null);
+            cylinderMod.Props?.Filters?.First().Filter?.FirstOrDefault() ?? new MongoId(null);
 
         if (!cylinderTpl.IsValidMongoId())
         {
@@ -181,7 +181,7 @@ public class RagfairLinkedItemService(
         var result = new HashSet<MongoId>();
 
         var chambers = item.Properties?.Chambers;
-        if (chambers is null || chambers.Count == 0)
+        if (chambers is null || !chambers.Any())
         {
             return result;
         }
@@ -207,7 +207,7 @@ public class RagfairLinkedItemService(
         var result = new HashSet<MongoId>();
 
         var cartridges = item.Properties?.Cartridges;
-        if (cartridges is null || cartridges.Count == 0)
+        if (cartridges is null || !cartridges.Any())
         {
             return result;
         }
diff --git a/Tools/MongoIdTplGenerator/Generators/ItemTplMongoIdGenerator.cs b/Tools/MongoIdTplGenerator/Generators/ItemTplMongoIdGenerator.cs
index 7feea8e1..6e01b325 100644
--- a/Tools/MongoIdTplGenerator/Generators/ItemTplMongoIdGenerator.cs
+++ b/Tools/MongoIdTplGenerator/Generators/ItemTplMongoIdGenerator.cs
@@ -358,12 +358,12 @@ public class ItemTplMongoIdGenerator(
         // Add mag size for magazines
         if (itemHelper.IsOfBaseclass(item.Id, BaseClasses.MAGAZINE))
         {
-            suffix = $"{item.Properties?.Cartridges?[0].MaxCount?.ToString()}RND";
+            suffix = $"{item.Properties?.Cartridges?.First().MaxCount?.ToString()}RND";
         }
         // Add pack size for ammo boxes
         else if (itemHelper.IsOfBaseclass(item.Id, BaseClasses.AMMO_BOX))
         {
-            suffix = $"{item.Properties.StackSlots[0]?.MaxCount.ToString()}RND";
+            suffix = $"{item.Properties.StackSlots.First()?.MaxCount.ToString()}RND";
         }
 
         // Add "DAMAGED" for damaged items
@@ -404,14 +404,20 @@ public class ItemTplMongoIdGenerator(
 
     private string GetAmmoBoxPrefix(TemplateItem item)
     {
-        var ammoTpl = item.Properties?.StackSlots?[0]?.Props?.Filters?[0]?.Filter?.FirstOrDefault();
+        var ammoTpl = item
+            .Properties?.StackSlots?.First()
+            ?.Props?.Filters?.First()
+            ?.Filter?.FirstOrDefault();
 
         return GetAmmoPrefix(_items[ammoTpl.Value]);
     }
 
     private string GetMagazinePrefix(TemplateItem item)
     {
-        var ammoTpl = item.Properties?.Cartridges?[0]?.Props?.Filters?[0]?.Filter?.FirstOrDefault();
+        var ammoTpl = item
+            .Properties?.Cartridges?.First()
+            ?.Props?.Filters?.First()
+            ?.Filter?.FirstOrDefault();
 
         return GetAmmoPrefix(_items[ammoTpl.Value]);
     }