OP...
Lots of opinions here. My two cents...
I purchased my M235i x-drive in 2018 with 38K miles and have ~96K on mine now. I am the 2nd owner. I am planning on getting at least 250K on mine, barring winning the lottery (which will be a challenge since I do not buy tickets) or having someone give me a new Base M3, in which case, I will immediately make the change.
This said, my car, despite being 2nd hand has performed very well. It was well cared for prior to my purchase and I am rather meticulous about maintenance, since I expect my cars to be able to last for at least 250-300K miles.
Like any car, the M235 has certain "flaws". None of these is significant to determine ownership. I am not going to detail them here, you can read the forum to get the details. Overall, the M235 is a very reliable and robust car. The N55 is essentially bulletproof and the M235 N55 benefits from robust internal components that enhance longevity. My only concern would be the extent of modifications to the car you are looking at. If these are "boy racer" mods, i.e. ECU mods, etc., I would avoid the car as it was likely thrashed by an owner. LSD, suspension and cosmetic mods are fine. The LSD is an especially sound mod to the M235.
If the car was well maintained, and you have objective evidence to support this, and the ECU has not been modded, the car is likely worth buying. As noted, I would try to negotiate a better price; however, in today's market, this will be challenging.
Good luck with your decision. If you decide to go with a M235, you will not regret it!
