You're in luck State Farm will insure any vehicle you buy for 7 days to get it home and registered if you have an existing auto policy. That policy is extra nice, because they won't insure the bus as a bus, but will to get it home. All you will need to show LEO IF you get stopped is your insurance card for your other auto, a current BOS, and signed title.
I had an accident at my very fisrt fuel stop when I bought mine. Cop showed up, I had my SF agent on the phone. Cop took my phone and asked "Is he insured right now?" My agent said Yes, cop handed me my phone, got in his car and drove off.