Uggg. So sorry you are dealing with this. I have a not very good story, well maybe (if you don't have them in your house, not so bad)? I need to proceed it with my daughter had zero tolerance for her situation. She had 2 very young (one newborn, the other 2yo) children and could not/would not risk them being bit -- she was concerned it was possible she would not know. My daughter lived in a very old neighborhood, with lots of brick houses. They were known for having bats, there were several houses with bat houses (you'd see tall poles away from their houses, with a bat house on top of it). The idea being the bats roost there instead of in their houses.
As far as your situation, I wouldn't touch that guano. Yes, it can be full of germs, etc. Good you have the bat people coming, let them do it.
My daughter's house had bats in the attic, and she could hear them in the walls (she has bionic ears, I swear), and at least twice they got in the living area of her house.
They are protected, but, you don't have to live with them. She had a bat specialist come, she was frustrated they captured the bats and put them in a little cage, and buckled them in the front seat. She said the bats were smiling as they drove away ("I'll be back smiles"). Your bat specialist should know the rules and what they can do. Around here, it depended on the time of year (breeding season). But removing from her home was allowed regardless.
In the end, she found out her house had been treated for bats before they moved in. It was bad, in the attic, and they come back (if they can). She thinks she had an allergic reaction (sinus issues) because of the guana, too. They put 'bat doors' on her house, so the bats could exit but not get back in. And they supposably sealed up the house so the the bats couldn't get back in (caulking all cracks and crevices). But she could hear them, and knew if they could get in the walls, it was only a matter of time before they got back in the house.
In the end, they moved - to a brand new house, new development. She disclosed the bat situation (some people don't mind 'em) and also had it fully treated (again). She said when they treated the 1st time, they did a 'touch up' since it was treated prior to her purchasing it (and she thought possibly why it failed).
But... if your bats are only outside, I think there are things to do to mitigate the situation. Bat houses, also they don't like light. I think keeping areas lit where you think they will hang out will help.
My other bat story. My cat brought 3 of them in my house (dead). I've seen a bat here once in 35 years (outside in my shutter when I was washing it). I don't know where she found them, but she did. We have a doggy door and she brought 3 of them in. That was a fiasco. All animals that had been in the house had to have rabies boosters (as a precaution because we just didn't know who else might have played with these darling presents). So 4 dogs and 2 cats all got boosters. They were all up on their shots but still it was recommended by the humane society. And we had the bats tested for rabies (they were negative). $65 a bat, but when I had the first 2 (just a day apart) and I said test 1 first (I figured if the 1st was rabid, I wouldn't bother to test the 2nd)-- they tested both for $65. A week later, she brought in bat number 3. I didn't know what I would do if this continued (it has not).
I think having the bat specialist come an learning more what you can do to mitigate will be good. How long have you lived where you are? And this is the first time you've experienced this?