If you can't drive or park a larger vehicle, maybe don't rent a larger vehicle. Rent a normal sized car and book motels.
Nothing more frustrating than being stuck behind muppets driving campers they have no right to be driving, crossing over into oncoming traffic, going +20kph below the speed limit, struggling to navigate a curve, and parking like a blind man on meth.
Yeah, that camping trip you planned for months is great and all, but now you're pissing off the locals and people who rented something within their driving abilities.
Being able to drive a Fiat Panda or Honda Civic in your home country is not the same as driving a Camper / RV in a foreign country, especially if RHD vs LHD.
/Rant