Most all Flying J's, Petro's, and TA truck stops have CAT scales. They'll weigh all MH axles and your toad also for about +-$8. Be sure to weigh with full fuel, water, empty holding tanks and all the stuff you carry with you. This will give you a worst case as you will usually be lighter than that.
Dave, Miss Sue & Lucy the Scotty
Big Easy Area.
2000 Monaco Windsor, 40' 2 Slide, ISC 350 HP.
2012 Honda Pilot or 1998 Blazer Toads
Aventa 2, Brake Buddy
The problem with CAT scales is most of 'em are BRIDGE scales (Rasied above ground on a bridge) and these are not really the best, You need weights side to side as well as front and rear.
http://www.rvsafety.com Follow the obvious links (Which last I looked were in a banner near the top) and they come to you with portable scales and other information, reasonable fee but they are more expensive than truck scales.
Or make friends with your local Diesel Smokey. Couple of beers and the job is done.
Home is where I park it.
Kenwood TS-2000 housed in a 2005 Damon Intruder 377