Dude another guy asked a similar question, use the search function.
In all honesty, you can get as much as you want, provided you get a dumb enough buyer. It all depends on who you are selling it to. I wont pay that much for it, knowing the PSP 3000 is launching soon. Max i would pay is about 1k. But there are some people out there who dont have a clue, about these things and so long as its cheaper then what it goes for in the shops, they will buy it.