One option I haven't heard anyone mention (because they're still fairly new) is MiniStays.

My tenant is also nonresponsive to all communications so they may not even show up at this point.

Some piece of communication is missing.  

Assuming your property is in Utah (like your profile indicates), here's the state law from a basic internet search:In Utah, a tenant who abandons a rental property without notice is liable for the lesser of the following: The rent remaining on the leaseThe rent plus the difference between the fair rental value and the agreed-upon rentThe cost to restore the property to its original conditionThe landlord can also remove the tenant's belongings and sell them if the tenant doesn't claim them within a reasonable time.

A copy of our current driver’s licenses (for both of us).Again, all the verifying documents have been submitted through Zillow, but now we are communicating with the wife via email (outside of Zillow).

They only communicate through chat and email.

You want them all to be able to communicate well with you and with each other.

We are in Tampa so a similar market.We provide a starter set which is clearly communicated to guests (thought some people do not like it and clearly do not read which you cannot help) generally consisting of:- 2 Laundry Pods- 2 Dishwasher pods- 2 Rolls of Toilet Paper per bathroom- 2 Paper Towel Rolls- 2 Trashbags- All soaps are refillable including dish soap, hand soap, and body washes/shampoos.They are expected to get their own should they run out of anything. 

You want a platform that has built in TCPA protections as well as a multiple communication channels besides voice such as SMS and email.

Transparency, regular communication, and clear milestones have been critical to making this successful.For those of you who are considering working with private lenders or want to improve your deal structure, I hope this gives you some food for thought.