добавил

ComputerHardwareStore/ComputerHardwareStore.sln

@@ -5,6 +5,8 @@ VisualStudioVersion = 17.7.34031.279
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ComputerHardwareStore", "ComputerHardwareStore\ComputerHardwareStore.csproj", "{D5DDEE2B-A0C4-430B-B00E-452BA1AB3DDA}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ComputerHardwareStoreDataModels", "ComputerHardwareStoreDataModels\ComputerHardwareStoreDataModels.csproj", "{48126915-C6D4-451C-BC88-39E3C50332B8}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -15,6 +17,10 @@ Global
 		{D5DDEE2B-A0C4-430B-B00E-452BA1AB3DDA}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{D5DDEE2B-A0C4-430B-B00E-452BA1AB3DDA}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{D5DDEE2B-A0C4-430B-B00E-452BA1AB3DDA}.Release|Any CPU.Build.0 = Release|Any CPU
+		{48126915-C6D4-451C-BC88-39E3C50332B8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{48126915-C6D4-451C-BC88-39E3C50332B8}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{48126915-C6D4-451C-BC88-39E3C50332B8}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{48126915-C6D4-451C-BC88-39E3C50332B8}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

ComputerHardwareStore/ComputerHardwareStoreDataModels/ComputerHardwareStoreDataModels.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

ComputerHardwareStore/ComputerHardwareStoreDataModels/Enums/OrderStatus.cs

@@ -0,0 +1,11 @@
+namespace ComputerHardwareStoreDataModels.Enums
+{
+    public enum OrderStatus
+    {
+        Неизвестен = -1,
+        Принят = 0,
+        Выполняется = 1,
+        Готов = 2,
+        Выдан = 3,
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/IId.cs

@@ -0,0 +1,7 @@
+namespace ComputerHardwareStoreDataModels
+{
+    public interface IId
+    {
+        int Id { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IBuildModel.cs

@@ -0,0 +1,10 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IBuildModel : IId
+    {
+        string BuildName { get; }
+        double Price { get; }
+        int VendorId { get; }
+        public Dictionary<int, (IComponentModel, int)> BuildComponent { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/ICommentModel.cs

@@ -0,0 +1,9 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface ICommentModel : IId
+    {
+        DateTime Date { get; }
+        string Text { get; }
+        int BuildId { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IComponentModel.cs

@@ -0,0 +1,9 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IComponentModel : IId
+    {
+        string ComponentName { get; }
+        double Cost { get; }
+        int StoreKeeperId { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IOrderModel.cs

@@ -0,0 +1,10 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IOrderModel : IId
+    {
+        double Cost { get; }
+        DateTime DateCreate { get; }
+        int StoreKeeperId { get; }
+        public Dictionary<int, (IProductModel, int)> OrderProduct { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IProductModel.cs

@@ -0,0 +1,9 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IProductModel : IId
+    {
+        string Name { get; }
+        double Price { get; }
+        public Dictionary<int, (IComponentModel, int)> ProductComponent { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IPurchaseModel.cs

@@ -0,0 +1,12 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IPurchaseModel : IId
+    {
+        double Cost { get; }
+        DateTime DateCreate { get; }
+        int VendorId { get; }
+        double Sum { get; }
+        public Dictionary<int, (IBuildModel, int)> PurchaseBuild { get; }
+        public Dictionary<int, (IProductModel, int)> PurchaseProduct { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IStoreKeeperModel.cs

@@ -0,0 +1,9 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IStoreKeeperModel : IId
+    {
+        string Name { get; }
+        string Login { get; }
+        string Password { get; }
+    }
+}

ComputerHardwareStore/ComputerHardwareStoreDataModels/Models/IVendorModel.cs

@@ -0,0 +1,9 @@
+namespace ComputerHardwareStoreDataModels.Models
+{
+    public interface IVendorModel : IId
+    {
+        string Name { get; }
+        string Login { get; }
+        string Password { get; }
+    }
+}