🎮 Buying a used graphics card, what should I actually check before handing over the money?

Found a used graphics card listed online at a genuinely decent price, noticeably cheaper than buying the exact same model new, and the seller seems reasonably legitimate based on his profile and a few previous positive reviews from other buyers, but I have genuinely never actually bought used PC hardware before and want to make sure I am not missing anything obviously important before actually meeting up to complete the purchase itself. A few things I already know to check from some initial reading, actually seeing it running properly in a live system rather than just trusting photos alone, checking for any obvious physical damage or genuinely excessive dust buildup that might suggest poor previous maintenance or heavy prior use over an extended period of time, and specifically asking directly whether it was ever used for cryptocurrency mining, since apparently that kind of sustained heavy continuous use can genuinely wear components down faster than typical regular gaming or general everyday use would. What I am genuinely less sure about is how to actually properly test it beyond just confirming it powers on and displays something on screen without any obvious immediate issues. Should I actually be running some kind of specific stress test program directly on the spot during the meetup itself, or is that generally considered excessive and unreasonable for what is ultimately just a fairly casual private secondhand sale between two individuals rather than some kind of formal transaction? Also unsure about a fair, reasonable way to actually verify the seller's claimed usage history beyond simply trusting his own word on it, since there is presumably no completely foolproof way to fully confirm exactly how heavily or lightly it was actually used previously before this specific sale to me. Planning to meet in a genuinely public place with my own laptop specifically to test it properly beforehand, which several people have separately suggested as a reasonably sensible precaution to take for this kind of specific secondhand hardware purchase. For anyone who has actually bought used PC hardware like this successfully before themselves, what specific checks do you personally consider genuinely essential before actually handing over any money for something like this?

Always bring a small USB drive with a free benchmark tool loaded on it to any used hardware meetup now, running it for even ten minutes on the spot catches thermal throttling or instability issues that just powering on and looking at the display never would reveal. Most reasonable sellers do not mind the extra few minutes if you explain why upfront.

Asked a seller the same mining question once and he flatly denied it despite the card's fan bearings sounding noticeably rough for its stated age, walked away from that particular listing entirely since something did not add up. Trust your gut on small inconsistencies like that even when everything else about the listing otherwise looks reasonable enough on paper at first glance.