Geico. They beat all hell out of the local MA insurers for car rates (and did the same for my daughter in California). Homeowner's is competitive with the local guys. Umbrella liability is notably MORE expensive than the local guys.Who is your carrier? I would be happy to get a quote.
Overall, I'm probably 20% lower than if I went all local. If I could get homeowner + umbrella local and Geico for the cars, I'd be in clover. However, EVERY local company that I've spoken to won't write the umbrella if they don't write the cars, regardless of the underlying car insurance levels. They're clearly worried about the car insurer cutting a deal in the event of an accident that leaves them open on a follow-up suit.