diff --git a/domain-model.md b/domain-model.md
index 653f474..c237081 100644
--- a/domain-model.md
+++ b/domain-model.md
@@ -1 +1,27 @@
-#Domain Models In Here
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+# Domain Models In Here
+
+## User Story 1:
+```
+As a supermarket shopper,
+So that I can pay for products at checkout,
+I'd like to be able to know the total cost of items in my basket.
+```
+
+### Domain Model:
+| Classes         | Methods                                 | Scenario                             | Outputs |
+|-----------------|-----------------------------------------|--------------------------------------|---------|
+| `Supermarket`   | `findTotalCost(List<Product> products)` | Sum up list cost of list of products | int     |
+
+
+## User Story 2:
+```
+As an organised individual,
+So that I can evaluate my shopping habits,
+I'd like to see an itemised receipt that includes the name and price of the products
+I bought as well as the quantity, and a total cost of my basket.
+```
+
+### Domain Model:
+| Classes         | Methods                                 | Scenario                |    Outputs    |
+|-----------------|-----------------------------------------|-------------------------|---------------|
+| `Supermarket`   | `getReceipt(List<Product> products)`    | Giving list of products | Console ouput |
diff --git a/tdd-domain-modelling.CSharp.Main/Supermarket.cs b/tdd-domain-modelling.CSharp.Main/Supermarket.cs
new file mode 100644
index 0000000..dc2ad0f
--- /dev/null
+++ b/tdd-domain-modelling.CSharp.Main/Supermarket.cs
@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace tdd_domain_modelling.CSharp.Main
+{
+    public class Supermarket
+    {
+        private Dictionary<string, int> _basket = new Dictionary<string, int>();
+        public Dictionary<string, int> basket { get { return _basket; } }
+
+        public bool Add(string product, int price)
+        {
+            if (basket.ContainsKey(product))
+            {
+                return false;
+            }
+            basket.Add(product, price);
+            return true;
+        }
+
+        public int GetTotalPrices()
+        {
+            if (basket.Count == 0)
+            {
+                return 0;
+            }
+            return basket.Values.Sum(x => x);
+        }
+    }
+}
diff --git a/tdd-domain-modelling.CSharp.Test/SupermarketTests.cs b/tdd-domain-modelling.CSharp.Test/SupermarketTests.cs
new file mode 100644
index 0000000..060b5cd
--- /dev/null
+++ b/tdd-domain-modelling.CSharp.Test/SupermarketTests.cs
@@ -0,0 +1,57 @@
+using NUnit.Framework;
+using tdd_domain_modelling.CSharp.Main;
+
+namespace tdd_domain_modelling.CSharp.Test
+{
+    [TestFixture]
+    public class SupermarketTest
+    {
+        [TestCase("Apple", 12, true)]
+        [TestCase("Banana", 5, true)]
+        [TestCase("Coffee", 8, true)]
+        public void TestAddNewProductInBasket(string product, int price, bool expectedBasketAddResult)
+        {
+            //Arrange
+            Supermarket customer = new Supermarket();
+
+            //Act
+            bool actualBasketAddResult = customer.Add(product, price);
+
+            //Assert
+            Assert.That(expectedBasketAddResult, Is.EqualTo(actualBasketAddResult));
+        }
+
+        [TestCase("Apple", 12, false)]
+        [TestCase("Banana", 5, false)]
+        [TestCase("Coffee", 8, false)]
+        public void TestAddExistingProductInBasket(string product, int price, bool expectedBasketAddResult)
+        {
+            //Arrange
+            Supermarket customer = new Supermarket();
+            customer.Add(product, price);
+
+            //Act
+            bool actualBasketAddResult = customer.Add(product, price);
+
+            //Assert
+            Assert.That(expectedBasketAddResult, Is.EqualTo(actualBasketAddResult));
+        }
+
+        [Test]
+        public void TestTotalCostOfProductsInBasket()
+        {
+            //Arrange
+            Supermarket customer = new Supermarket();
+            customer.Add("Apple", 30);
+            customer.Add("Coffee", 20);
+            customer.Add("Cheese", 70);
+            int expectedTotalCost = 120;
+
+            //Act
+            int actualTotalCost = customer.GetTotalPrices();
+
+            //Assert
+            Assert.That(expectedTotalCost, Is.EqualTo(actualTotalCost));
+        }
+    }
+}
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