Get your taxes done using TurboTax

This works in TurboTax Online.  Type '1099-K' in the Search area, then click on 'Jump to 1099-k'.

If you see your 1099-K on the Summary page, Edit it.  If not, you will see 'Did you get a 1099-K?'.

On the next screen, choose 'Type it in Myself'.

On the next screen, choose Personal Item Sales.  

Continue, and enter info from your 1099-K.   Be sure to check the box indicating you sold 'Personal Items'.

If you had a loss (or no gain) on your sales, on the next screen indicate that.