Just like any other car a lot depends on how much of the little stuff you can do yourself.
If you have to take it to the BMW dealer for every little sound or wiggle. I can predict it will be VERY EXPENSIVE to maintain
I have spent only about a thousand on real maintenance in two years. I need to do about another $500 this year. All of the rest I have spent has been jewlery for my little silver Mistress
BTW I bought her for $17,000 two years ago
The depreciated price from then to now is still about $17,000.