I know there are individuals working on data analytics for this as I've been contacted by a few who have early models they're wanting to test.

how sustainable is this model?

Some of our initial baseline, no-go, criteria when we first listed were: 600+ credit score, no evictions, no bankruptcy, and income 3x rent... however, after finding that very few interested parties were eligible to even "enter a review phase" of landlord verifications etc, we loosened up a bit and went to an objective scoring model that I tweaked from a few ideas obtained after speaking to both rental professionals in my local area and some on this forum. 

I also modeled out what the investment might look like if the exit cap rate increased compared to the purchase cap rate.2.

Depending on what model I use, I obviously get a different DSCR.

And yes, as of now I'm leaning towards a cash flow model and I need to figure out how to execute that plan.

:Intriguing model – Fits the niche of offering a housing alternative that is cheaper than a studio apartment.

with the subscription model, i pay less for VRBO bookings than Airbnb.

I have had several of my short-term owners go to a self-insure model (i.e. they only get liability insurance on paid for properties) in recent years.

Where I invest, there is quarterly garbage fees LL pays, which get billed back to tenant.Sounds like this model would work for you too.