Re: Insure as what?
Speaking of...my apologies, ShortBus, but they were out of that form at the DMV so I can't get you the exact Minnesota requirements for RV plates. I will try again later this week.
On the CDL thing (which you did a pretty fine job of)
seating for16 people including driver (15 is actually legal)
over 26,000 lbs
under 26,000 lbs tow vehicle, but with a trailer over 10,000 lbs that causes the combination weight to exceed 26,000 lbs
air brakes without RV plates...check about if you need it under 26,000
Something worth noting is that most of our fullsize buses have a GVWR of over 26,000 lbs. My 66 passenger bus has a 30,000 lbs GVWR. If I registered it just as a box van (very few seats) I would need to do so as 26,000 lbs or less to avoid CDL requirements. Obviously I would need to weigh less than that amount as well. In every state I know of you can change the GVWR of the vehicle. The DOT is going to look to make sure the tires are of adequate capacity, you are not exceeding axle weight limits, and you are not exceeding your tagged weight from a tax basis.