Well, Where Angels Fear, I know little about the actual houses of bats, although the university in my city has hugely popular ones that attract dozens of spectators each evening at dusk.

https://www.floridamuseum.ufl.edu/bats/

And, my veterinarian is a bat expert who also has a bat house in front of her clinic. Alas, I know very little about animal bats and way more about human bats than I ever wanted to know.