In this picture I would like to point out the two sofits that have been circled. With a structure that has dormers this is typicaly the area of entry that is most found. I have seen gaps from less than a quarter inch to nearly a foot. For bats it does not take much of a gap linear for entry. Raccoons will use this area as well if the opening is large enough.
The corners of your homes can be good ingress and egress for squirrels, chipmunks and mice. The channel will allow them access to your sofets.
Chimney flashing that has separated from the roof will give easy access to squirrels and bats.
Underneath the collers on these metalbestos chimneys will give squirrels access to your attic area.
Alth0ugh not often used often dryer vents can be another access point for squirrels. It is very important to keep dryer vents clean. Biggest reason is because of the fire hazard, but also when it is filled with lint in prohibits the flap from closing all the way which in turn lets unwanted pests in.