What can I realistically test in ten minutes before buying a used handheld?

I found a used handheld gaming system listed for $180, about $70 below the other local listings I have seen. The seller says it works perfectly but wants to meet in a grocery-store parking lot because it is convenient for both of us. He is willing to let me test it, but I do not want to turn the passenger seat into a repair bench.

The photos look clean. The screen is on in two of them, the charging cable is included, and the seller has shown the storage page. That rules out almost nothing I am worried about. A device can display a menu while having weak buttons, noisy fans, unreliable charging, wireless problems, or a battery that drops ten percent during the drive home.

I have bought used consoles before, but usually from friends or stores with a return window. A private sale makes every missed problem mine. At the same time, I know no ten-minute test can prove years of future reliability. I could spend so long trying to eliminate risk that the discount stops being worth the effort.

My current checklist is: inspect the body and ports, boot from fully off, test every button and stick, connect to Wi-Fi, launch a game, check audio, plug in power, and watch for obvious screen problems. I would bring a small game I already own if the device supports that. I would also confirm that accounts and locks are removed before paying.

The seller has been responsive and has not pressured me. The low price may simply reflect wanting a quick sale. It may also reflect a flaw that appears after fifteen minutes, which is exactly how long he does not want to stand in a parking lot.

What would you prioritize if time is limited? Which failures are deal-breakers on the spot, and which cosmetic or battery issues are reasonable at this discount? I am prepared to walk away. I just want the decision to come from a short, useful test rather than from becoming emotionally attached the moment the startup sound plays.