I was really referring to folks who get their units washed at home or at campgrounds by those traveling with their pressure washer rigs. I should have been more precise in my questioning. My dealer frowned on pressure washing the units as damage could occur to the finish and possibly water getting inside. That made me afraid of the drive thru washers which those of you who have used, seem to be happy with.
I checked my unit over carefully after the young man finished washing it an had nary a drop of water inside. I especially checked around the air conditioners. Even dropped the inside cowling and checked gasket seal. Was quite surprised that they were snug and had plenty of gasket showing. There is even yellow markers around the gasket to show how much is there. Seems lots of people have problems in that are so was pleased to see I'm not one of them.
The young man said he does a lot of trailers and airplanes. Said he thought I should get it done at least twice a year and would only charge $100 after the initial soaking.