Infinity. Just do maintenance and be happy. That’s why my brother just sold his e36 328 convertible at 287k miles to a friend of ours so he could make room for his newly acquired corvette. His own words, not mine: “if I had the space, I would’ve kept it. That car was a blast to fuck around with since it was cheap enough to not care as much about, but still fast enough to have fun.”
Haven’t done it myself, but hoping someone talks about the M school! Sounds like a blast!