If possible wash front of mh off in early morning when dew has them softened up. use a long handled brush and plenty of suds using anti spotting car wash. Might have to let suds set a minute or redo.
Don't wash it in the hot sun and use a filter on the water hose, at many places. It's not like you're washing the whole coach. Ask first if you think there is a problem.
Any dust or dirt and pollen can scratch the paint and glass.
I waxed the glass with Mequires, Spray Synthetic wax when, I had the time and polished it off good. It helped a lot.
Micro fiber towels or cloths really help clean the glass, on the end of a squeegie or one of those floor cleaner heads, Brain dead right now, with Armor All Glass Cleaner, no ammonia, when it is inconvenient to wash off the windshield but not a dusty cap.