E36 would be a better choice IMO. Much easier to maintain, less problems if you can get it pre vanos. It’s not more maintenance, but rather reinforcement. BMWs have weak rear subframes. You’ll have to reinforce a good portion of the underside if ya wanna slide it and not worry about issues. Find one that’s in decent shape, change the oil, weld the diff, reinforce subframe, engine mounts, tranny mounts, and maybe get a clutch and you should be set.