Today I talked with an agent from Allstate in California (initially I talked to one in FL) and they are able to write policies for school bus conversions both professionally and home grown.
As an example:
2007 IC CE300 costs $100 and change per six month policy for 100/300 LIABILITY ONLY
Add Comp/Collision to that by a "professional" ( I've done several home remodels and building projects) with a $45K value after conversion (self-valuated) and the COMP/COLLISION policy for six months goes to just under $300 inclusive of liability.
The FL agent's contact info is:
( . . )
The CA agent's contact info is:
NOTE: They are full aware that this bus is registered in VT as a MH with a CA address.