[MWMM3]

What are some tips / things to look out for / anything that would help me with a purchase of an M3? I want to get a 2010-2012 M3 with 60k miles, but I feel like if shit goes down the hill I might not be able to afford it. I really like the M and I will take precautionary maintenance for the Rod Bearings but I'm not sure what else goes down with this car. Everyone says getting one without insurance is an L but I wanna hear personal experiences of owning one for 60k+ miles, not recent purchases.

Mostly looking for:
1. Length owned for, mileage driven, and maintenance/repairs and their cost
2. Tips and things to look out for when checking out M's in the lot, like how do I know how well its taken care of? Oil Analysis? History? etc.
3. Any bad experiences / regrets?
4. Hows the reliability going into the 100k mileages????
5. What mileage should one usually let their M3 go at due to the costs outweighing the other factors?
Personal experiences/stories in regards to owning your M3 and how it affects your wallet are welcome. I just wanna know how much it costs to own one and if its worth it.