public void CheckOut()
        {
            // Arrange
            const string  STATE = "South Dakota";
            const decimal EXPECTED_TOTAL_WITHOUT_TAX = 1400.00M;
            const decimal EXPECTED_TAX       = 63.00M;
            const decimal EXPECTED_TOTAL_DUE = EXPECTED_TOTAL_WITHOUT_TAX + EXPECTED_TAX;
            const int     SHOPPER_ID         = 1;
            const string  SHOPPER_NAME       = "Tiger";
            const string  SHOPPER_STATE      = STATE;
            const int     QUANTITY           = 1;

            Shopper shopper = new Shopper(SHOPPER_ID, SHOPPER_NAME, SHOPPER_STATE);

            const decimal CALLAWAY_IRON_PRICE = 900.00M;
            const string  CALLAWAY_IRON_NAME  = "Mavrik Irons";
            Item          CallawayIrons       = new Item(CALLAWAY_IRON_NAME, CALLAWAY_IRON_PRICE);

            shopper.Add(CallawayIrons, QUANTITY);

            const decimal CALLAWAY_DRIVER_PRICE = 500.00M;
            const string  CALLAWAY_DRIVER_NAME  = "Mavrik Driver";
            Item          CallawayDriver        = new Item(CALLAWAY_DRIVER_NAME, CALLAWAY_DRIVER_PRICE);

            shopper.Add(CallawayDriver, QUANTITY);

            // Act
            decimal ActualTotalDue = shopper.CheckOut();

            // Assert
            Assert.AreEqual(EXPECTED_TOTAL_DUE, ActualTotalDue);
        }