You know as pet owner, rat owner.. I know rats as pets are great. But would never cuddle a wild rat!
You won't find many rat owners to disagree with the fact that yes their wild cousins are a plague and a pest. They are really successfull and..destructive.
Hell even as pet they are destructive..oh well.
I would say use steelwoll, yup already mentioned but if I noticed anything is that they don't like things that prick in their noses. Sensitive creatures
When a fellow says, "It ain't the money but the principle of the thing," it's the money. -- Kim Hubbard