.$6800 /mo income- $3,200 /mo debt= $3,600 /mo $2300 /mo expense at 35% total expense (probably high)+ $900 /mo PITI____$3,200 debtThis would be me thinking out loud.

You are using the cash flow of the property to obtain debt financing to acquire your target property.  

You also need a good debt to income ratio. 

Then, at some point where the bank won't loan anymore to me due to my debt ratio being too high, I plan on selling the SFHs I have, cash out, take a big chunk of that money and buy an apartment complex ( 6 units and +).

Let me make this a lot easier for you. when you take over the debt on a property, you are not generally looking to give the seller anything other than debt relief. 

I hate debt and that is one other hang up I need to overcome.Thanks, Dan

A tip given to me by my lawyer - the Navy Marine Corps Relief Society can give low interest loans to active duty members to get out of debt in order to help them keep their security clearance eligibility. 

Doing this to the extent that debt service washes out all cash flow seems very risky.

It could be the difference in a couple thousand dollars in your pocket a year.Also, good credit goes a long way, but a good credit score in conjunction with a good debt to income ratio makes quite a bit of difference.

To give you an example, there's something called the loan level price adjustment, which in layman's terms means that those who will not owner occupied, have a less-than-perfect credit score, higher debt to income ratio, etc., pay a higher rate.