I can give you some more specific advice on permitting processes and building. 

A lot of people shrug off Modular and Manufactured but they are both cash cows and help avoid longer construction times, higher material costs and less permits. 

The city is very open to this setup, with a clear permit process: $500 initially, plus a $100 inspection fee.

According to planning, only 1 and 1/2 story is permitted in this neighborhood.There are some consideration yet to be taken at this point.

I am a senior outreach worker for Oxford House in Arizona.

Need to keep in mind STR license / permit restrictions when evaluating.  

Addtional Insured status for you on the SL's Insurance policies (General Liability, Professional Liability, Workers Comp., etc..)2. 10 day notice of cancellation from the SL's Insurance carrier3.

Many times, if you wish to hold the title in the name of an LLC, you may end up with less favorable terms or even find that it's not allowed.If you do find a loan program that permits taking the title in an LLC, it's essential to consult with your attorney and accountant to understand how to proceed.

Louis]Single-family home building permits serve as a leading indicator of future housing supply trends.

Being so close to the bases, you could make change it at some point from a long-term rental to short-term (for families coming into town) or mid-term (for military contract workers) and that would earn you more.For now, I would keep saving and invest in something else and leave this as it is.