Cost to have someone wash your FW

We keep our FW in a storage area which makes it difficult to wash from time to time. Anyone pay someone to wash your RV? Don't need a complete detail with wax, just a wash, including the roof. It's also time for me to do the annual roof caulking and it's obviously good to have it clean before we do that. Never considered paying someone, but at our old place we could keep our RV on our property. Not the case since we moved here. Just looking for a general idea before I start calling around. Thought of taking it to the dealer for a detail and caulk but my guess is they would be pricey.