I have made several quilts for our local school's music department fun raiser. This year, I let them know how much material costs I had in the quilt. They started the bidding just under the price, and ended up getting three times that for the quilt. I don't think they even knew how much the materials cost, and did not know where the price should start. The quilt was a tshirt quilt made from the Band directors t shirst.
Maybe we need to let the party know at least an estimate for the material on items we donate.