I dislike chemicals and what it can mean in a body so....
Here is a natural mix that we use and it works well. A sealer jar with Apple Cider vinegar..and a handful of parsley. Break up the parsley...stuff it in the jat with the vinegar and into the fridge for 24 hours. I use a personal spray bottle...works really wlel. Yes, there is taste on the lips and an odour..for about a minute.Once it dries...no left over smell or taste.
As far as inside an RV? Get the mosquito screens from Home Depot and the like...smaller mesh. Easy to switch out.
Gary Haupt