I am sorry you have gotten burned more than once and I agree it might be better to just donate $20 or whatever the spirit moves. Unfortunately, sometimes people think that because it is donated it isn't worth much. I've had similar situations when chairing craft fairs for our church. I think I fairly priced the items that I had made, but I didn't let the price go below a certain amount, unless it was the end of the day and sales had been very slow. I itemized what I had put into the items and asked for it to be shown as a charitable donation. In the end, do what you feel is right, but don't sell yourself short either.