The funny mouse story, not funny!
Our home is 1848 here in the valley we were the first home, it was a cabin. Since then additions 1912, 1920, 2007. Lots of cracks around the outside of the home. My hubby loves that foam you use to fill cracks. He has totally fixed the mouse problem.
Since we tore off the 1920 addition we have had no mice. Not upstairs at all. Our main basement is in the 1800's but is in good shape, DH has used foam down there too.