I moved to a lake house last fall. Had like 6 bats living in a small attic space. I know they can become a MASSIVE problem. Took about a week to find out where they were coming in and out. LITERALLY a small spot under a shingle that you could barely fit the handle of a butter knife. So I put a nest cam on the roof to confirm. First I tried a bat tube. Those things suck unless it is in an ideal location for its intened application where the end of the tube hangs 3ft in mid air. I swear those bats would spend an hour walking around finding the end of the tube to go back in. FINALLY I had to wait till they all flew out at 9:30PM (ON THE DOT). At about 10PM I'd crawll on the roof (stunk like bat urine - UGH) and caulk in the spot. Had to do this a few times.
Then I paid $1400 to have a black plated mesh thats bent in a Z screwed all around my ridge vent. Made by a company in northern Michigan. Have to be a contractor or builder to buy. I had a contractor friend purchase and drop ship to my house. Then paid a roofer $800 to install. STEEP PITCH 2 story. I wasnt getting up there. Ridge vents are like an effing welcome sign.
GOOD LUCK. The bat exterminating theives in my area wanted $5000 and didnty do clean up and DEFINEATELY didn't go to the lengths I did.
Now the neighbors have bats POURING out of a big gap in the soffits of thier house. At least they aren't in mine. That told me "they're YOU'RE bats"
then judiciously wrapped them in the towel, and took them outside to bat freedom.