With the income levels you described and presumably the housing assistance from the military, you would benefit from buying over renting.

This sets you in a class above as you actually have some dough and presumably, some experience. 

If you have the cash to invest on the second property, it would be a good idea to do so out of state since I presume you cannot house-hack again until next year.

I presume you are saying "yes" to the 3 lists in 3 counties means you need 9 numbers, but what about the other part?  

. $70k purchase price w/ seller financing, 100k rehab cost, refinance immediately after rehab, $175k, 70%LTV, presuming an appraisal price of $250k.  

Expect your loan to be underwritten using an appraisal that is based on the markets long term rents, not the higher income you presumable expect to collect operating as a STR.

AND this is crazy important because--guessing, presuming, and assuming are not how you get to reliable numbers for a renovation. 

@David Ward I presume you've read ad nauseum about this very subject in other posts.

I presume you know about the 30 Day Stay book?

The reference to April 1992 is presumably the date the law took effect, and it says simply that any recorded instrument (lien, mortgage, judgement) that was recorded before April 1992 will not be endowed with the benefits of the law, or subject to the law (so in other words, security interests recorded before that date will be subject to the law as it was beforehand).