This may be a dumb question but, since I would not trust a GPU card "on eBay" anymore than I would a guy selling the Golden Gate Bridge for scrap, where will th

This may be a dumb question but, since I would not trust a GPU card "on eBay" anymore than I would a guy selling the Golden Gate Bridge for scrap, where will these cards appear - how will people trust them? (Or more accurately - where can I pick up a couple?)