They don't go for a lot. A totally stock PM7 goes for around 150. With upgraded board, around 175-200. Even with a UL frame, you generally won't get more than 250.
I'd probably start out asking 225 and would hope to eventually sell it for 200. And if I were you I would sell the parts kit separate. You'll get more selling it by itself than you would bundling it with the gun.
Originally Posted by pbkidminion
I would honestly just keep it and use it, they're awesome shooters, and the price-performance ratio can't be beat
Agreed. For the 200 bucks you'll get for selling the PM7 you're not going to find many used guns that shoot better, and certainly not any new ones.