Rodents often get under San Diego homes through torn crawl-space covers, open vents, gaps under doors, loose flashing

https://brooksbhkr926.northcrestbrief.com/posts/why-you-should-never-vacuum-rodent-droppings-in-your-attic-2

Rodents often get under San Diego homes through torn crawl-space covers, open vents, gaps under doors, loose flashing, and openings where utility or A/C lines enter exterior walls.