@shredder Welcome to the Forum! I get the strong impression (this is not an analysis, it's an opinion) that buying a second hand emtb is a bit of a lottery. I'm very sad to have to say it, but based upon what I read in this forum, it has to be. I have only sold one emtb and it was flawless and sold as such at 3500 miles, with confidence, but I have to accept that it may have failed the day afterwards. It didn't, or I would never have heard the end of it from the buyer! He got a good deal and so might you; I'm sure that most do so.
Likewise, I have had zero problems over almost 2100 miles on my current emtb, but it could fail tomorrow! I'm only counting battery, motor, display, software etc as failures. So far so good.
But if you scan the threads on here there are no end of motor failures, battery problems and so forth. Many are on multiple motors (but they seem to be mostly those coming with a Specialized bike). I know other motors fail but they don't seem to be as common. Then there are the Shimano motors! I have not done a deep analysis, but they seem to run ok until, all of a sudden they don't, and if they are out of warranty, you have an irreparable motor. If within warranty you might be OK or you might not as you might still not get a new motor - it all depends up who Shimano feel like being nice to today. Let me be clear I have had two flawless Shimano motors over 5500 miles and my personal experience is to be envied (or is it normal?) I honestly don't know whether I have just been lucky or maybe it's because I don't ride through deep water, wash with power hoses, spoof the motor into thinking it's going slower than it really is, and other chicanery. Likewise, I don't do massive drops, not even medium drops, so that must reduce the hammer onto the bearings. Who knows?
Based upon what I have read in this emtb Forum, I would say the following: Don't get a Speccy at any price. Only get a bike with a Shimano motor if it is well within warranty (check it and if it is not a transferable warranty don't buy). After that pretty much any emtb with pretty much any motor should see you right. I am assuming that my little moan at Speccy and all Shimano motors may (even though I have only ever owned Shimano and had 100% success) smoke out a few spirited and closely argued objections in favour of the motors used by Speccy and of course the Shimano motors. PS: I very much doubt that I will be buying another bike that sports a Shimano motor, not because I don't like the motors, because I do. But because I have come to dislike their customer service policy. I will vote with my wallet and probably buy a Bosch that at least has the merit of being repairable! (There are other motor brands).
But most of all, do your homework!!!