Selecting A Motorhome With Enough Tow Capacity

It looks as though you are on track with your research. You didn't specifically mention whether you wanted a new or used motorhome, but there are many class As and specifically the E450 C that have 7500 lb tow ratings. With the longer C you may run into GAWR issues, since the roughly 700 lb tongue weight will add about 1000 lbs to the rear axle. A properly set up weight distributing hitch will help alleviate that, if the motorhome manufacturer and hitch allow the use of such a hitch.