Cost at a Flying J truck scale is $10.50 for all platforms. This allows you to weigh the steer axle, the drive axle, a tag and the toad all at the same time for the same price.
Cost for individual wheel weighing at Pomona will be $60.00.
Either one will get you most of the info you need. Make sure you have a full tank of fuel and are campground ready. This will give you the most accurate reading. Consult the weigh tables from the mfg, FMCA or RVSEF's site and inflate to the highest weight per axle as Scott indicated prior...good luck...Dennis