Who is in charge of procurement?

In short, the previous owner made a deal and sold the house while they were still living for monthly cash payments until they died.  

I live in a small town in eastern Arizona, about 7000 people, and we have a pretty serious shortage of rental properties.

You should reach out to @Melissa Haworth she can get the actual numbers/rents on STRs in the area to help run your comps.Each building is different, each area is different, it is important to find accurate data to make good decisions.

And what timeline can lender #2 close in? 

In Dec 2020 I purchased a 1% property in San Diego.  

I’m in a similar position with similar goals.

What you describe sounds a little like a BRRRR (Buy Rehab Rent Refinance Repeat). 

And in terms of the unit - we own 4 others in a 3 mile radius and are very familiar with comps.

Sounds like internal accountability is really important to you!