I have used Hiscox for several years. Their customer service is top notch, and I can get a certificate of insurance issued for a client within hours. $1 mil general liability policy for two Phantoms (primary and backup) will run you about $400/yr. I think a single Phantom is about $300/yr. No deductible on the policy, but if you smack your drone into the side of your clients facility, not having a deductible probably isn’t going to be much of a comfort. They also have hull coverage but I don’t carry that on my policy. Hiscox has the option to pay for your policy in monthly installments, so there is little reason to not be insured.
If you are using your drone commercially, letting your clients know you have a dedicated aviation policy will also give your business an extra measure of credibility.
Fly safe.