Donโt believe in pressure washers as mostly they are not needed. If you have a garden sprayer, mix up a batch of water, Dawn dish washing liquid ( a couple of really really good squirts) , and a cup of bleach per gallon of water. Go up on roof and spray the mixture on the roof and slide toppers, brush with a medium brush, let it set for about 15 minutes for the bleach to work, and then rinse liberally. If there are any spots left repeat on those areas.
Next, build a carport for the RV. (Include a power plug of at least 30 amps).
Tom Wilds
Blythewood, SC
2016 Newmar Baystar Sport 3004
2015 Jeep Wrangler 2dr HT