Buying second-hand

I have a chance to buy second-hand, expect to have some 30-60 minutes to test the device at the guy's home to check for any issues. Can you please suggest what to pay special attention to, apart from the obvious ones, such as audio, midi, USB, buttons, and knobs, if powers on upon the first attempt?
Heads up on any issues specific to Force would be appreciated.
Thanks

Does it have good audio outputs? That has been a problem.

Is there a hard drive installed - and if so, does it come with it?

Does the SD card slot work properly?

Which firmware version is installed, and are any additional sound modules installed? If not, how much of a pain in the rear will updating it be?

Those are the things that occur to me beyond key functions.

Thank you. Looks like there are some quality issues around Force. would not have occurred to me to check SD card slot; the more valuable to know.

I wouldn't call the SD card slot a major problem, but it's a real pain in the butt if it doesn't work, so it's worth checking. Shouldn't take more than a minute anyway.

Honestly, aside from the audio output problems, it's been a fairly solid unit. I don't think you're running a major risk, here.

Make sure ALL the input and outputs work without audio issues