"OCCC (Occupant and Cargo Carrying Capacity) (for Motorized RVs only): This figure states the maximum allowable weight of all occupants (including the driver), plus the weight of all food, tools, full fresh water tanks, full LP-Gas tanks and personal belongings. The maximum allowable weight of passengers is based on the number of seat belted positions in the motorized RV. The regulation also states that the “tongue weight of towed trailer counts as cargo."
"Load Carrying Capacity Reduced: The regulation also requires dealers to state on an amended or additional label the total amount (in pounds and kg) that additional options or changes to the RV have decreased the OCCC or CCC. The amount stated is limited to the total weight of all additions or changes made by the dealer ‘prior to the first sale’ that are the ‘lesser of 1.5% of the GVWR or 100 pounds’."
But as steveownby points out, the most important thing is doing the math between the empty weight of the coach and the gross axle weight ratings. How much does the coach weight full of fuel and fresh water before you buy it and subtract that from the gross weight that the coach is allow to carry.