[sullic]

The 2006 Porsche C4 that I had for 13 years did not have a dipstick. That is quite common today and not an inditement against BMW engine design.

All higher end sport cars cost a lot to maintain. You have to know this going in.
If you do the required maintenance actions on the car, there is no reason to think this car will be too troublesome. Yes, the parts are expensive, but so are parts for equivalent Audi, MB, Porsche, etc.

Yes, you can sell before warranty ends and that can make sense for many. I sold my 2019 MB C63S just after my warranty ended to get my 2024 M8, so I know that game, but I did that as I was just looking for something new and I felt that this might be one of the last truly good-looking BMW's. Also equipped with a awesome V8 engine.

Tons of folks are still running the older C63S of my generation with no issues. I still follow those boards as I did enjoy the car. Tons will run these cars for years with no major issues. Just be prepared to pay for major services, or as downeykp suggests jump before the end of warranty.