If you decide to inspect your home for entry points, you should definitely start by carefully investigating the building inside and out. Mice love squeezing in tiny spaces like holes around windows or cracks in the foundation, which we often ignore and assume that they are & too small for any animal to go through. When you find gaps in your foundation, you can fill them with silicone caulk to make sure that mice won’t use it as an entry point. The same applies to spaces between the bricks, as they allow mice to get behind the interior walls of your house. Another crucial step is making sure there are no gaps around door or window frames. If the building is quite old, you may want to consider replacing the windows rather than fixing them again and again.