BMWs make for VERY fun cars, unless you are fooled into a faux BMW with a four cylinder engine.
Early 2000s E46... best looking production four-door EVER. You can park it next to anything, anywhere, anytime and it will still look good.
If the owner is being unpleasant it is probably due to the fact that he/she is still seething over the last mechanic bill.
If you buy a used BMW you should know that immediately upon taking ownership it is obligatory to change every-single-last hose, tube and gasket under the hood. This is not debatable. This will buy you about 6 months of leak-free time.
New steering arms and rear suspension should always be included in initial buy price...
BMWs are fun.