Isotope only sells new comics & we don’t buy used or vintage comics. We don’t grade old comics & don’t keep up with the used market so we wouldn’t even know what a fair price for your vintage comics would be. Fortunately the Bay Area has lots of other stores who do deal in vintage comics and could give you a better idea about what you have. Best of luck!
Not sure was visiting San Francisco l July 2018 and did not ask if they buy comics or not when I went to Isotope.
Comics you made? Yes. Back issues? No.
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