I find it more helpful to track on my total cash into the deal (inclusive of furniture, amenities, etc), so cash on cash and monthly net cash flow are the two metrics I find are most informative when I'm looking at a purchase. 

LTR Backup Plan: I want to ensure that if the STR route doesn’t pan out, the property could sustain itself as a long-term rental (LTR).

If you are 75% complete rehab you are very close to ordering furniture IMO.3 - Look for safety hazards - i.e. uneven steps etc.If your time in town is limited I would focus on these 3 areas.  

who owns the furniture?

If your priority is building wealth sustainably and positioning yourself for long-term financial independence, I’d strongly recommend considering properties like duplexes, triplexes, or even quadplexes.

These numbers sound decent but whats the condition of the property and is the $925/month rent sustainable for the neighborhood?

Scratch & dent furniture & appliance outlets are your friends!

The sustainability test is that 3/4 of units need to cover 75% of the mortgage from my understanding.

Like others mentioned above the sustainability for his model does not seem to be there.

If it’s empty, consider staging it with a few key pieces of furniture.