The whole rabies part is what I've been worried about, I have two cats and they are the ones who always find the bats. I would hear them jumping around trying to catch them while the bats flew around the room.
We figured the walls because a house I lived in when I was younger had a bad infestation, where they lived in the walls and would come out of the small gaps in the walls. We didn't stay there for long... but my step father found a hole behind the stove and patched it up. He told me to keep looking around the apartment for more holes and patch them up. And we are sure they are coming in through the roof, the apartments upstairs aren't used and sometimes the landlords have found birds in there so the bats are probably getting in upstairs the same the birds do and find a way downstairs. These are very old apartment buildings, they are some of the towns first buildings.