public async Task Add_InvalidObjectPassed_ReturnsBadRequest()
        {
            // Arrange
            var biddingProperty = new BiddingProperty()
            {
                AskingPrice = 350000.00M
            };

            _controller.ModelState.AddModelError("Title", "Required");

            // Act
            var badResult = await _controller.Add(biddingProperty);

            // Assert
            Assert.IsInstanceOf <BadRequestObjectResult>(badResult);
        }