My landlady has close to the 17 cats and they live real close by. I love her to death, but she said her boyfriend started feeding those Neighborhood Cats and now they all hang around. They aren't neutered or spayed so they keep reproducing. There's really nothing I can do about it although I've gently suggested getting the cats fixed to stop making more babies. They keep the cats on the back porch and they feed them outside. They wander around here and I make sure that my cat stays safely indoors. One of them is a scruffy looking male cat and I know that he would get into it with my declawed Newt.
As for Herb... He sounds like a real shady character and I would definitely keep some locks on the door and be careful. Who pays triple the rent for nothing, right? Great job.