The easy answer is to first call your own insurance company and see what they have to offer (assuming you use an agent). When it comes to any kind of commercial insurance I would highly, highly recommend you use an agent rather than a phone center, DIY insurance company. Right now I have almost everything insured through Erie (they don't offer in every state) but I have used State Farm, Allstate and Lloyd's of London as well. All through agents - I want an individual I can call that I know personally to give me answers to questions or help shepherd claims through.