Not sure if this answers the question but I would pay a little more for a card I can touch and hold in person. I would also pay a small bit more from a reputable auction house. Both have built in safety nets which ebay doesn't offer. And I do mean only a little more. Maybe I would pay an extra $20-$40 for a card valued under $500. That being said my biggest fear on ebay is a seller's friend bidding/shillling on a card and then me winning it. When/If I go to resell it then the price suddenly plunges. I know it can happen at auction houses too but it's not quite as likely, as many auction houses do some policing (believe it or not), and though it's not perfect, it's better than nothing. At least buying in a straight private sale (or at a store) I know I am not being run up
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