So that may force me to adapt my model. 

If your seller second balloons, which most do, I highly recommend that the balloon lasts at least 5 years or it will impact the bank's terms to you. 

However, if someone was to alert them they could choose to do an inspection and actually force you to remove people until you get under that limit.

It's actually better to invest out of state in my opinion so you're forced to outsource and delegate your real estate functions to others which will allow you to scale quicker.  

The pressure on a forced air furnace is not likely enough to cause any issues I would imagine.

These provisions will force me to sale my assets prematurely for a loss or will force me to distribute them where I will be subject to taxes and penalties.

BRRRR's rely on forcing equity, they have nothing to do with interest rates.

Doing it on a rent to own or a wrap instead of just buying it for her gives him the ability to show that process as net zero to lenders in the future and not impact his future lendability.

Hello,I have a question just out of curiosity, suppose there is a development of highrise apartments may be within 2 to 5 miles of radius with say 700 apartments , how does it impact small landlords with 2-4 units close to a major metropolitan city?

., have a tremendous impact on your return.