public void ShouldReturnFalse_WhenNotApproachingPayInLimit()
            {
                Account sut = new AccountBuilder().WithPaidIn(2000m);

                Assert.IsFalse(sut.IsApproachingPayInLimit(1000m));
            }
            public void ShouldReturnTrue_WhenApproachingPayInLimit()
            {
                Account sut = new AccountBuilder().WithPaidIn(2000m);

                Assert.IsTrue(sut.IsApproachingPayInLimit(1750m));
            }