I won a competition and received a camera package with retail value at $20,000. I sold it to someone in New York city at $15,000. How does this transaction affect my tax return of the year? How much approximately do I owe in tax for this sale???
Lastly, how do I report this transaction at the end of the year? I'm a freelance photographer, I don't sell stuff for a living.

I'm very concerned and would like to ask someone here for help. Any answer would be much appreciated.

Thanks a lot in advance.