Some people have actually gone so far as to have an outside wall taken out, a bat house installed (prevents ingress into the house at large) and then sealed up save the small bat entrance. They enter, hang, sleep, exit. There is a tray that can be slid out, washed, and re-inserted. This is not for the faint of heart, as the potential for exposure to rabies and other toxic goo is high, but some do it nonetheless.

I am actually considering something like that. At some point, I need to strip my home down to the studs regardless. I might just have a box on a lever-pole that allows lowering and cleaning.

Being attached directly to the house means that each time a new pup is born and hits the teenage years, it has to learn it doesn't have dominion and eventually stops complaining when I make noise.