How do you come up with a bv for an unpriced card? I have an 04 Fleer Genuine orange AARON BROOKS 5/10 that I'm looking to trade, but I have no idea what kind of $ amt. to look for in return. Beckett lists it as unpriced. I don't want to screw anyone with a ridiculous price, but at the same time I don't want to give it away.

Thanks for any help!