Sealing entry points is the most essential long-term step to prevent a comeback.
If rats can't find food or water, they are less likely to stay. How To Get Rid of Rats - Busy Bins HOW TO GET RID OF RATS
Use chew-proof materials like stainless steel mesh (1/4-inch), steel wool (packed tightly with caulk), or concrete. Avoid using only expanding foam, as rats can chew through it. Sealing entry points is the most essential long-term