How much could I get for a 4 month used GTX 690?

legacyBIOS

Honorable
Sep 10, 2013
74
0
10,660
Hey guys. I'm thinking about switching to dual GTX 780s, and I was just curious how much you guys think I could get for a 4 month used GTX 690. It's in mint condition physically and performance wise (zero problems).

Thanks in advance!