Investors & landlords

Another issue that I run into when I start to enter all the transactions one by one is that they screw up on the calculation of the Cost Basis. Probably because all that they do is ask which lots the stock was sold from without asking how much from each lot was sold. So it ends up being that they overestimate the loss by 2x. So then do I have to make an adjustment for that loss? 

Here's what it calculates for me

But then here's the actual loss. Only $600.