Don't think I'd mind a squirrel in the attic but would need some research. The possibility of chewing cables would certainly be a worry...

The only animal in this house we have declared out and out war on to the point of getting the council in twice and them putting poison in the roof space has been with rats. I've seen the odd one the cats have killed outside - usually younger ones and with beautifuly clean brown silky fur. They are nothing like the images of a creature you may see portrayed as living in a sewer and in filth but they have no place whatsoever in the house.

We are in a farming area and back on to a field. If the rats want to live out there and brave the cats, I say good luck to them (even if one did eat the sunflower seeds) but there is that one step to far.