Step 1 – Doing that now. Using expanding foam mixed with powered cement.
Step 2 – Using “glue traps.” For some reason mice around here did not go for peanut butter.
Step 3 – Two major reasons there are no cats here: Two 80lb Labs that use cats as toys.
I have actually caught two snakes inside the house. Guess they chased mice into their holes and followed. Now they worked and dogs did not bother them. I did not know about the snakes until they were caught in the glue traps. I hate snakes so keeping them inside the house is out.