However I have always assumed that the Detroit market will come roaring back someday (soon or in a decade or two, not sure) and I'm jealous of those who know the market well and can invest strategically.

Every part of REI involves some sort of analysis which is than followed by a strategic decision.  

A strategic interior renovation plan was immediately implemented upgrading units in-house efficiently creating significant value.

Send your spreadsheet or whatever you use as your strategic plan.  

I currently am house hacking a property (renting our main house while living in ADU) in the North and East neighborhood and strategizing on how I can buy my next one.

Outside of revenue, there are two important factors that you need to consider when you own/control many properties; asset protection and strategic tax planning.

We believe in strategic diversification and it works when done right.

I was in the Navy from 2012 to 2016 and worked on F-18 aircraft.

What you’re asking though would be a lot cheaper to build hangers for GA aircraft.

Which is why a lot of successful investors will tell you that Rich Dad got them started, but it was their own hard work and strategic initiative that made them successful.