Looking at your competition, what is their physical vacancy, their turnover (related, but not the same), evictions/bad debt, loss to rent (how many units are not renting at market), and concessions ("1-month free on annual lease).  

Lastly, 1. depending on where the property is located, you might be able to raise rents and still be inside the rent cap. 2. if the property currently has debt, most Agency debt have restrictions that survive the LURA and may further impact you ability to take the property out of the affordable housing stock. 3.Are you under and HAP agreement?

You personal debt to income is very high.

I've had credit for less than a year and haven't filed income taxes yet, my first filing will be for 2015.This way I will have the income, experience, business history needed to get loans and show operating capability, and I could use that company for all our real estate transactions.Another advantage would be having the manpower to purchase buildings and keep the management "in house", while at the same time having some income from the existing management  contracts they have in-place.I am looking for a company with at least 5 years in business, cash flowing 300-400K, healthy financials and no debt.

As long as the property is seeing actual cashflow each month, someone else is paying down your debt for you and you are building equity on someone else's hard work (tenant's job pays your debt).

To pay off as much of the credit card debt as possible.

The underwriter looked at my case and find big gap at debt to income ratio.

Lots of current debt on the property including maintenance fees, RE taxes and an assessment from the hoa.

In your example, a $5000 +/- on expenses can swing the cap rate from 10.5 to 12% may not seem like much but depending on your debt cost could be significant.Lastly, some items should be easy to estimate (taxes, insurance, etc..)

Sell 2 duplexes (4 units) at 90k a piece and almost pay off the debt and hold 6 units.