It’s not really enough for me to be comfortable leaving my full time job so I’d like to learn how to use the equity tied up in these properties to scale up & get to where I want to be asap. 

If you're comfortable with living on the outskirts of Sioux Falls, the no money down USDA loan may be a perfect option for you.

So it really comes down to risk management and how comfortable he is with debt.

I believe this market cycle is topping, and one should tread very carefully before investing more money into an 'unsure' property.That does NOT mean to stop investing; just make sure you aren't trying to catch a falling knife in an unsure environment. 

This includes understanding your budget, securing financing if needed, and determining what you can comfortably afford.Research is key.

I’d buy there as much as I can comfortably afford regardless of MTR strategy.

When you are investor friendly it means you understand the metrics of the buyers property search.I have seen so many agents get comfortable and simply add their new buyers to the "Hot Sheet" and they blast the buyers with properties that do not even fit the buyers cash flow needs or budget.

Maybe you could compromise by finding a property that you can live in comfortably but also has rental potential (like a duplex).

As you keep learning, you'll get more comfortable with the numbers and figure out which strategy works best for you both.

This very comforting device alerts you if the noise level is above a threshold.