Your insurance co should be able to add an additional coverage for the RV. Might be time for a new ins co.
My insurance is nothing special, but covers anything I am driving, not just the vehicle I own. However, I have not checked if this also covers the RV extras or just the chassis.
Odd that a rental RV has no on-board generator. Keep shopping around. I would rent an RV that is ready to go. By "renting a generator" do you mean you will have a portable one? That will be a hassle and a HUGE mistake - for a newbie RVer to have to set up and secure (from theft) a generator each day. Not worth it.
Pack light if you are flying half the trip.
Generally in an RV it is best to use propane appliances and not electric. Electric requires to be plugged in or to run the generator. Propane is always there and cheap to use.
Are you planning to see the country along the way or just getting to the destination fast?
Staying in a campground every night is not necessary and can take up huge chunks of time that could be spent driving or doing something else. Expensive too if all you will do is pull in, sleep then get up and leave. Walmark parking lots offer the same and no check-in required.
A lot of travelers just drive, and when it is time to sleep or pull over for an RV cooked meal they just find a parking lot along the route and a level spot.
