by the way - while prepal is cool, it's dreadfully inaccurate imho and hasn't had new products added for what, 5 years? so it's the best there is and definitely helpful, but don't base TOO much upon what you find there.
it doesn't take into account the difference between pay now and auction prices on ebay for example, and it obviously isn't aware of the true sale price of classified sale prices (such as craigslist) and as such is really only accurate as a guide for trying to sell on ebay.
I see people ask huge prices for things on craigslist because prepal told them it sells for that. well guess what? art pro mpa units don't go for $238 or whatever. they're ancient units now and as they get older will have more issues... they're frickin chinese (sure they sound great, that's not my point). mpa golds might go for that used, but they're not listed in prepal because they're too "new" (how many years old are mpa golds now?)
that's off the top of my head, but the point I think is valid even if my example may not be. don't trust it entirely, and don't go paying those prices because the site says that's what they go for.
use common sense, check out how old a device is, and so on. prepal tends to lump newer models in with older ones under the same older product heading and then the prices get skewed and are no longer useful imho.
and no - I'm not jilted because I couldn't afford that used mpa gold I saw on craigslist ;-) really. not me.
cheers,
Don