You can spray a little water on them and they will usually leave. A professional cannot do it but a homeowner can certainly spray off his home and if it happens to run the bats off, well se la vie... they will not die, they will just live somewhere else. Put up a bunch of bat houses, you need to lay them on the ground for about a year before putting them up,, handling them as little as possible. People do it all the time, you just don't publicize it and you certainly don't film it or ask the "authorities".
I don't know man... they just left. Since they were gone (I would film
that), I added screen."
BTW, I would not run them off while they had young. I am even hesitant to trap coons or opossum' right now (springtime) and relocate them for fear they may have young. I don't want to carry of a opossum to an area when it does not know where to get food and I am not going to start poking around on it to look it it's pouch... I'm not even getting close to touching a coon. I did see a coon hanging on my birdfeeder in the middle of the night two days ago. I will probably trap it and check it for signs of suckling... if none, it is going far away. The home owner did the right thing in this case.. with babies involved... and it really made no difference to the homeowner to wait a bit.
J