There is a cleaner manufactured here in Maine called DE1000. Camper dealers in the area carry it and it works!!!!
You can use it straight for issues such as your window surrounds, awnings, bugs on the front, etc. Cut it 75% and it is safe for rubber roofs and general cleaning of the trailer. Also use it for removing bugs from the front and mirrors on the truck.
I will give you the address of the plant and dirtibutor where it is made if you want, pretty sure that they will sell and ship it to an end user.
I have turned several RVer's in the area into firm believers, all they have to do is clean the trailer one time. They come to me after and are amazed how well it cleans, why didn't I tell them about it before, etc. :-laf:-laf
If any of you are interested, let me know and will post address of company.
I am not affiliated with them at all, they just make a fine product and I will spread the word.