Get your taxes done using TurboTax

It depends. This would be considered an investment sale.  When you entered the 1099-K you had the opportunity to enter the cost. You just need to edit the 1099-K and enter your cost right below the 'Proceeds'. See the image below.

1. Open your TurboTax Online/Mobile or TurboTax Desktop return.
2. Search > 1099k > Click the Jump to... link > edit beside your 1099-K for StubHub