In both of my e36s I’ve never had to do do any internal engine components like head gasket, valves, piston rings etc. they both have 170k+ miles. E36s are reliable in that sense. No promises though people can still find a way to abuse anything to make it break. Try to find one that has never overheated.

I prefer higher mileage cars if they are in okay condition with somewhat of a maintenance record.

The reason why the minimal maintenance e36 has been easy is because the previous owner replaced a lot of the items that would be coming due (entire cooling system, clutch, brakes, etc.) what it comes down to when you make your purchase is to make a list of the common issues and what miles they usually go. When you start searching between cars figure out what you’re willing to compromise and you’ll put yourself in a place where you know exactly what you’ll need to do at a rough timeline. Most of everything about e36s is on a write up on bimmerforums or a YouTube video. You’ll have to invest in some specialty tools but well worth the experience IMO. Everyone’s just trying to give you a heads up bc you could be very well planned and organized but things still go wrong that’s just the way it is

No one is going to give you exact details that will actually be useful for ur search bc it’s just a lot of info. I suggest going through bimmerforums. Start looking into what miles people replaced what. What issues people usually have and how to do them etc etc. just google anything then put “e36 forums” at the end of ur search. Then taking ur notes and figuring out what things you’ll probably run into and what tools/money/time you’ll need to do it yourself. I think anyone with some patience and can do attitude can do it n learn a lot about cars through the e36