so I have a Mets ball from recently deceased Al Jackson inscribed to his "roomie" with about 14 other 60s Mets signatures as well. I have two questions. First, I want to get a better idea how to value for auction. Sounds odd but is a multi signed ball worth less than a single signed ball? Would a good method to value be to look at past sales with each of the names, add up and divide by say half the total? I know condition is important and do not want to bother with a card shop and their cut. Also, there is provenance from the inscription, but it is not certified. I find that a waste of money for items not pristine. But if I was to get certified, how much do they charge for a ball with 15 signatures? None are Hall of Famers but some are lesser Mets stars. Thanks for any advice.
