If it's just a good washing you need, a quick and easy solution is a "Blue Beacon" Truck Wash. They are located across the country centered near truck stops. Cost me $33 and they do a beautiful job. Make sure to tell them "low pressure" with the wands. For the most part, they already know this with RV's and don't blast around seams, windows, etc. they pre-soak as you enter and hand wash entire rig. It's a good fix while traveling and keeps the bug guts from becoming glue blobs. Downside...you may have to wait in line for 20 or 30 minutes during busy periods. Well worth the time and cost. We have one a few miles from the house and use it after every multi-day trip.
2018 THOR Chateau 35SF
Two Labs, Bugsie & Blondie