Leaderboard

I'd try a range of things, and I'm sure others will have more to add, but I would: Check the camera physically to make sure the screen works, buttons, EVF, etc I'd update the firmware straight away to the latest Put on several lenses and test that they're recognised correctly and the AF and OIS are working After putting in a new battery and formatting a memory card in it, I'd pick the best quality normal mode (24/25/30p) and do a long recording on it of something that has a lot of movement in it (a great test is putting three still images on a timeline each at 1 frame and then loop the video).. if it records without issue for 20+ minutes without anything odd happening that's good, but if you have time I'd test until the card fills up or the battery dies I'd also do the same but on the highest frame rate mode Check the files are playable in the camera and work on the computer If it passes all of the above then it's unlikely that it has some lingering issue that isn't also present on new copies as well.

Aside from launch day preorders like the BMPCC4K, I buy almost all my cameras used from major retailers. You’d be amazed how many cameras get returned just a couple weeks after launch. Like new condition for 10-15% off. I stress test them quickly just to make sure there isn’t some defect. Typically, anything rated 9 or higher from B&H is indistinguishable from brand new.

I've had some great bits of luck recently by using search terms that reflect what a person who didn't know what they had would use as a listing title - 'camera light' and so on... then sorting by Ending Soonest.