I wash mine at home, I usually wash it twice a year, once at the beginning of the end of the season. I treat my roof at the same time. I use a wash/wax combo and have had good results in the short year we have owned it.
I use the washwax.com stuff or I have used the truck wash Blue Beacon they do a good job only cost $27 for my 43ft 5th wheel. The use brushes to wash and only a mild spray for rinsing.
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2015 Siera 377FLIK
2014 Ford F350 KR
Maggie the new Chihuahua
Cricket the Chihuahua RIP
Steve & Jojo
I'm in West Yellowstone at the Yellowstone holiday rv park and they allow you to wash wax while here . in fact getting ready to do it today it's been a couple months . some allow it some don't but have never stayed at a place yet that didn't .
We take ours to the blue beacon truck wash near us. $30. Not perfect but better than nothing. We tell them to not get close with the pressure washers. No issues using them for almost 4 yrs now. We then bring it home to compound areas if necessary and then do a spray in wax with meguiars ultimate spray on wax. We do wash the roof by hand at home before going though.
If you can't bring it home and no truck wash near you, there are waterless solutions available.
I normally wash my class C at home but on this trip after 3 weeks on the road I took it to Eagle Truck wash. The front end of mh was black with bugs and for only $38.00 They washed it for only $1.20/ft it was pretty good.