One of the trapping methods we use for squirrels, is called a excluder. Squirrels usually have more than 1 entry point, but typically they have 1 that they prefer to use dailey. When sealing up a house for squirrels,  we seal up soffit insets, gable vents, builders gaps, fascia ends, etc. We leave 1 place for the squirrels to go into the attic and that's where we install the excluder. With this type of trap, it catches the squirrels whether they're coming out of the attic or going back in. Another benefit of that is that we know we caught the nuisance animal and not just some squirrel in the neighborhood. We're KenCan and we love what we do and so do our customers.