Most policies that I am aware of allow you to add several additional insureds to your policy, so that may be the best way to go. Contact your insurer. An important question to ask them when you do, is the effect of adding the “additional insured” to your policy. More often than not, when you add others to the policy, if a claim is ever filed by one of your additional insureds, that reduces the amount of coverage available to you if you should need to file a claim. Not really a big deal, but definitely something you should be aware of.
I hope this helps.