Around here we are blessed with two types of Wasp's that like our trailer. One builds nests out of mud and the other builds a paper nest. The paper nest is really dangerous if they get up into the exhaust vent of the heater or the refrigerator.
I have installed screens every where that I can and they still get in.
In June this year getting the TT ready for a trip I found six nests. One inside of each awning arm. Two inside the cover for the spare tire. Two up under neath the slide out and one inside the door of the hot water heater.
I know to be careful with the spray because if I don't knock them all down the first time they will give chase. So, I sneakly climb up the ladder to shoot down inside the awning arm and one out on patrol came back and nailed me on the side of the face. Luck no sting just an impact that caused me to dismount the ladder in record time.
Signed
Another wasp killing Bob