My car was stolen from my apartment. can i sue the apartment manager?

That stinks. Unfortunately, I don't think they are liable, I mean if you rented the apartment and it said there was security, and then they stopped doing it, yeah, then you could have a case, but usually they aren't responsible for stuff like that. But they must have some kind of insurance, slim possibility if you try that angle, you might get something, it wouldn't be a lot of money to them. Good luck.