I have looked on this feature like the take a penny/leave a penny at many stores.
There have been constant comments on the various lists, on what do I do with my excess origami models. This is your perfect chance to get rid of those excess models and for them to find a good home. Your throw away model could be someone's treasure. When Arlene and I were in Germany, the contents of the table were constantly changing as models appeared and disappeared. Mark Kennedy