@futurebird Jeez. I have some immediate ideas - drippy bathroom faucet, for one - but this is quite a humid climate, lots of coastal fog.
When I locate them, how should I proceed? Can I convince them to leave, or have they doomed themselves?
Also, how would you advise preventing future incursions - like, what are the common points of ingress that might need maintenance? There are lots of small things here that need TLC, priorities are useful.