There are cracks between the foundation and where the house sits on the foundation (house is 30 years old).I think mice have been entering the house here. What do I use to fill these cracks so the mice do not get in, that doesn't cost an arm and a leg.
Answer:
First you stuff the cracks with course steel wool because that's about the only thing they won't chew through, and then you caulk so air can't get through either.