Everyone held up their end of the bargain on the ones I've been a part of. We do a "Christmas Trade" each year on PA. You put your name in the hat and the someone picks who sends to who. "What" is up to the sender but it must be made by the sender and finished. It involves bows, sets of arrows, sets of stone points, knives, quivers, etc. I sent an osage static recurve to one guy and received a nice leather possible bag from another.
Generally you find out the draw weight(range) and length of whomever you choose to send it to or trade with if bows are involved. The only problem that I can think of is with each persons expertise and the perceived fairness of the trade by each participant. I try to go into a trade with the thought of getting someones else's handiwork without thoughts of monetary value. Pat