Mice are super tough, blocking access points is a big fixer. When we purchased our home the previous owners had let them really get into the house. Steel wool, foam, and replacing any worn down wood helps. I also found and I know how wild this sounds but we have been looking for solutions that don’t harm other animals mouse birth control which is supposedly very effective. Haven’t tried it yet but have plans to put some out in the spring. https://conntraceptol.com/?gclid=Cj0KCQiA8aOeBhCWARIsANRFrQFo7sFTBIZLdKTfqLlqvzEy0Je21DcIe6P0ws3CjlmAaBJT-vbWfNgaAvFlEALw_wcB