Mortgage lenders will qualify you for a higher purchase amount for multis than they would on a single, because they will count the rent you will be making on the other units as additional qualifying income for your loan application.

Contractors, unless you have a working relationship with them, normally do not want you bouncing ideas off them.Understand what their hourly rate is, have a discussion with them that you are okay with paying them an hourly rate if they walk the property with you and provide you a scope of work along with an explanation of what you can/can't get away with in regards to improvements.ask them if you go with them, if they can credit you the amount that you paid.Once you develop a working relationship with a few contractors, you can bounce ideas off them and expect quality responses.I do not invest in New York.Best of luck. 

the note is converted or exchanged for credits?  

If my target would be low income residents, are there any grants, tax credits, or funds available to help me with the conversion? 

After communicating with a prospective resident (Google Voice #, usually by text), with just a name, telephone number and email, the applicant can pay $55 to provide us with a background, eviction and credit check.

The only other option I see is a short sale, if you don't need to purchase for a few years and don't mind a temporary credit hit to save the $60k.  

Additionally, regarding the legal structure, an LLC seems to be the most suitable option for our situation.

Renting it out while strategically leveraging the equity could be the best path forward.As @Jaycee Greene said, DSCR looks at your credit rather than DTI.

Alternatively, if the bank ( assuming there is a bank) is fine with it, you could negotiate a credit and escrow the funds to be released after you do it yourself.  

For a $300,000 property it could be $30,000.Then, do you have that much cash or credit available to you, in the event of a Due on Sale call?