In the flow of listing tickets I am never asked about my purchase price (as in what I paid) for tax reasons. If I go to the listings page and select edit listing I can see a box where I am supposed to be able to enter that price but it is greyed out and I cannot enter any value in there at all. I have called Stubhub a number of times and nobody can understand that I am not having a problem with my listing price but rather the cost to me price. I don't know hoe to go about having this fixed without an effective means of contacting the company.
It’s your responsibility to track your profit or loss for tax purposes. While it would be helpful you don’t need Stubhub to activate that field.