public void TestCalculate() { //Given var sut = new Reservation(); sut.CheckInDate = "2019-09-17"; sut.CheckOutDate = "2019-09-19"; sut.Rooms = new List <Room>() { new Room { DailyRate = 50M }, new Room { DailyRate = 60M }, new Room { DailyRate = 70M } }; //When var actual = sut.CalculateReservationCost(); //Then var expected = 360M; Assert.True(expected == actual); }