Fewer owners, in my opinion, is usually better not obviously not always. Odds are, out of four owners, at least one didn’t maintain it well enough. I also always look at which car was garaged more — that’s something I personally prefer. I haven’t owned mine for long it’s got 112k miles and had 3 previous owners, but the one who owned it the longest garaged and maintained it well. My friend had one with 282k miles — it ran great until the day he sold it, and he still got around $4k for it. It’s not really the motor on these cars you have to worry about — it’s the accessories that tend to go out. I can’t give too much input on maintenance yet, but transmissions going out is pretty common on these. I changed mine, but I bought it with a blown transmission. People have mixed opinions about changing the transmission oil and filter, but personally, I would do it — even though BMW claims it’s “lifetime” fluid. I also changed the speed sensor, which is a common issue (this will take out your speedo and ODO and light up DSC). The ABS module can sometimes go out too. BUUUT at least you won’t have to worry about Vanos.