If your agent/broker is knowledgeable about those types of products and has them available, it's likely more efficient for you to implement a single "master" policy for your properties.   

Technological advances creating more globalized economies and efficient means of communication (radio/phone mass adoption vs. internet and tech mass adoption).These are just some of the few uncanny similarities I am seeing between these time periods.

Even though the cash flow from a single unit is/was a little lower, there are efficiencies and appreciation that you will get in these properties instead of a single families. 

Be proactive in your communication.

And communication is key with what you expect of your tenants.  

Variance in between my top 5 go-to lenders is usually like 0.25% highest to low, usually there's 2-3 of them tied for first place (exact same rate, +/- $500 in closing costs), so you go with whomever the service/speed/communication leader is.Today, the high/low variance for those exact same 5 lenders is 1.5% to rate!

Even when I have an empty unit, I prefer scheduled tours- showing up on time and being able to communicate with me are part of my screening process, and I feel it's safer for me too.Hope that helps.

I have not sent any formal communication to my tenants.

I want to communicate that I am going to help as much as I can in the event that someone loses their job.

If a tenant needs to flexibility and are a decent and communicative tenant it is worth giving the situation some attention and working harder to manage through the difficult period rather than giving up on them.