This is an old question but I wanted to respond for posterity since Tiggersmom's answer is patently wrong. Verbal agreements are legally biding EVERYWHERE in the United States, but specifically Pennsylvania since that is the state this question is about. It isn't an issue of whether a verbal contract is legally binding, though, it's a question of proving one existed. As the old saying goes "A verbal contract is worth the paper it is written on."In PA specifically, a verbal lease is entirely enforceable in landlord/tenant court.
Verbal agreements are not legal, anywhere, and are rarely taken as a binding contract. Unless there's a recording or a video, or a signed, & written document. Good luck.