Tough finding motorhome insurance in massachusetts

Taxachusettes has it's own rules. Companies writing policies there, have to be based out of there. So a lot of companies dont bother setting up splinter operations in a commonwealth that has rules specific to it only.
Years ago I had an easy time getting a policy there but found that my "big name " insurance company was actually a tiny Mass only subsidiary when the Military transferred me to another state.
You are likely limited to only a few options, I suggest you Private message jplante4 for insight.