I've seen a few places like that, but surprisingly nothing was alive there when I saw it - not even dead carcasses anywhere to be found, just dirt of all kinds imagineable. Even the kitchen sink with dirty dishes that had been covered with boards to serve as a shelf for 2 foot tall stacks of paper had any signs of mold - just dried up food from 20 years ago.
I grew up in that only with a dozen cats that were never quite house trained. She's doing fine if it's not a bio hazard. Leave the woman alone. Its called freedom.
However I do now believe in the Critical Mass Theorem. If you can't find it when you need it you might as well not have it.
