IMHO, A method with a reasonable cost and ease of install follows. Have a fabricator build a shelf on the back of the rv. If has a rear bumper that can be modified as well if you concerned about a rear end collision mount it high. You can also fabricate a shelf that rides above the tanks on the front of the trailer frame. A Honda 3000 weighs 134 lbs, dry. A good shop can build a unit to that easily would support 175 to 200 lbs. Run a 30 amp cord to the regular power port on the RV. The Honda has a remote start as an option. Set your RV A/C to and start the gennie as needed. The 3000 does not immediately send power when started, as there is lag for gen to come up to speed. Should be able to get this done for under 3k and you now have a power source when dry camping.
