I let Possum do their thing around my house. Two or three nights a week, my IR cameras video them walking the top of the stockade fence around my property. One night, I videoed a cat standing there, watching a Possum chase down a small rat and eat it. I have no problem with the critters. The only issue they create for me is that I cannot put down rat traps, out of concern for the Possum and cats that go on rat patrol at night.