I recently bought a signed poster from another collector (not on this site) and it came back as not authentic. I have already emailed the seller to let him know I would like a refund and to ship it back to him. This is the first time I have had an autograph come back as not authentic and I think that the seller should pay for the authentication fee since they sold the item as authentic. Can someone who has been in this situation tell me if that's normal practice or if I am going to have to fight with the guy to get my money?