Again, this seems very common in the outer boroughs of NY for low income families, and am just curious. 

Despite the extremely low LTV ratio, multiple bankers I have spoken with, keep telling me that home equity lines of credit can only be levied against a primary residence, and not against an investment property, or portfolio.

In low rent markets a rough estimate of the expense, not including debt pay down, is 50% of the rent.  

If this is something you want to do, make sure you go 100%, if not, then the success rate is very low for anyone looking to get started, but this is true for any business you'd like to start.

I have seen some with short programs with low/affordable tuition. 

Your capex and maintenance is likely low. 550 renters are gonna be tough on a property

I was thinking of trying to use the 1031's to purchase 1 or 2 properties out right, or the other idea i was recommended by another investor since i am still young was to purchase the properties w/ 15yr mortgages since they still have very low interest rates vs 30yr loans and purchase a few properties that still cash flow with the 15yr loans with enough pay down with the 1031's.

By doing this you are creating a very low risk cash flow instrument. 

I am not too worried personally about the rain as none of my properties flooded during the 2015 flood, but there are a lot of low lying flood prone areas in Columbia.  

You haven't described a scenario that would qualify for one of the exceptions, so a "straight no" is the correct response.......Also, you know that FHA loans aren't the only low down payment options out there, right?