HITCH CARRIER:
I've had good experience with
Discount Ramps in the past. You'll want something like this:
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MOTORCYCLE:
Yamaha XT250 dual sport. Under 300 lbs. Easily carries two and is freeway legal (barely). Can go just about anywhere. Easy to ride on and off pavement. Has grown-up sized wheels & tires. You can see over and around traffic. Kick it up a notch and go with a Yamaha WR250R or a Kawasaki KLX250S.
If you're just putting around the neighborhood any little moped/scooter will do. But, it sounds like you actually want to go places without having to unhook the motorhome. To me that means motorcycle. Those oversized 500+ cc scooters are plenty powerful enough to tour around on but are too heavy for your hitch.
And OP, if you don't have two wheel experience I'd highly recommenced you take a motorcycle safety course. Not sure about other states but in California a motorcycle safety course certificate waives the riding portion of your DMV motorcycle license test.
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