Let me know how you would like to communicate

Once you can communicate that to an agent, they should be able to tell you which coverage will give you those results with your type of portfolio. 

He does the communication.

Once you establish that face to face contact, they are more receptive to working with you, releasing relevant information, and communicating. 

The biggest problem with low-income rentals isn't necessarily the tenants, it's the ineptitude of the landlord in screening and effectively communicating with the tenant base. 

The moment they think a red flag comes out the deal is done, no more communication.

Your time would be much better spent communicating directly with the executors of the estate.

If their communication skills are lacking then they do not have your best interest in mind and will not work in your favor, but rather for their own income. 

So you know they bother me when they happen to me.My thoughts on small claims in your area probably wouldn't be helpful because it's probably different than my area.If I was in your situation, I would document why I kept their deposit and I'd only communicate this via US Mail and I'd do it within the time frame proscribed by law in my area. 

Given the circumstances, I would suggest you either notify him via text or Email — whichever way you typically communicate with him more frequently.