I've had Bugsy, a cat and my service animal/emotional service animal. The ADA rules are correct. I've used it to travel by plane with my cat (planes are a huge trigger) and to bypass rental restrictions. However, if a potential landlord protests or seems like he will harass me more than normal, I go elsewhere. I don't need the added stress. Sometimes I've been known to offer an extra deposit and I tell them that I clip his claws on a regular basis. I try to make the potential landlord as comfortable as possible with the decision to allow me to keep my cat.