@E-and-J0, what you describe sounds familiar. AMICA declined to renew us for similar reasons. Many insurers simply aren't equipped -- or just aren't willing -- to take on the added risk of multiple short-term guests who would be more likely to file a claim should a mishap occur. So we've just gone through the hunt, and here's what we learned.
Airbnb claims to offer $1 million in liability coverage for all hosts, and your premiums are covered as part of the host fees they take with each booking. If there's a claim and Airbnb pays, great. I'm not willing to bet my retiremment on it, though.
Our local Farmers agent wrote us a policy through Farmers, and added a "business use" provision for our casita and stipulated it's a short-term rental. We got $2 million in property liabilty and another $2 million in umbrella coverage. (As you know, umbrella policies follow your automobiles, so we had to move our auto insurance to Farmers.) The good news is that for the cost of what we were paying for $300K personal liability and standard auto coverage through AMICA Insurance, we were able to get many times more liability coverage from Farmers -- and with eyes-wide-open coverage of our Airbnb space.
Farmers operates a specialty insurance company called Foremost Insurance. They can set you up with a Lloyd's policy, which is a special kind of insurance designed to cover unusual properties. Some Airbnb folks insist that you aren't truly covered unless you have a Lloyd's policy. http://www.foremost.com/
We also got a quote from a local broker who writes a lot of STR policies. He quoted us an expensive Llloyd's policy combined with traditional auto insurance. There may be someone in your area who has experience working with short-term and vacation rental folks (I'd Google areas in your state where there are lots of vacation rentals -- resort areas, etc. -- and look for brokers in those areas. Then dial a couple and ask if they have experience finding coverage for STRs. You'll probably end up wiht a Lloyd's policy.)
Finally, we also got a quote from Proper Insurance, which specializes in vacation and STR insurance. They will write you a $1 million General Commercial Liability Policy -- it too is a Lloyd's policy though in Proper's case it is essentially a business insurance policy. If your Airbnb property is also on your home property, Proper will need to include your main house in the coverage. The difference with Proper is that they really treat it as business insurance: If anything your guest does causes a loss in your neighborhood (their dog bites someone, or they shoot off fireworks and set your neighbor's house on fire), you're covered. Same goes if your guest borrows one of your loaner bikes and hurts himself. You're covered. This is generally NOT true with traditional policies, where the coverage stops at your property line. Finally, they include loss of income insurance of up to 6 months if you have a major loss (incident, flood, etc.) and have to go several months without the income you would have received from your Airbnb rental. We worked with an excellent guy there named Ian Smith. If I ever get the sense Farmers will not properly honor our STR claims, I'll probably go with Proper. https://www.proper.insure/
Hope this helps! And don't stress -- there are options out there, and you'll find one.
Carl and Diane