What do I do about my apt whenmy landlord is leaving?

I admit, this apartment I live in has never been in good shape but it's gotten worse and worse. I went out of town for 10 days and I come back to plumbing problems, bed bugs, and news that next month I'm getting new land lords. My current one, doesn't seem to care (And why should he) about my problems. He just come sin sprays some stuff for the bedbugs and then leaves. I don't know what to do. I've asked him to please check the apartment about the plumbing too but he seems to be avoiding me. He keeps blaming me (and my roommates) saying it's our fault the plumbing is messed up.... but that doesn't fix the problem. I'm at the end of my ropes and I can't afford my bathroom to keep flooding or to call a plumber myself. I don't know what to do. help?