Since you appear to live in Brooklyn I assume you will rely on a 3rd party property manager.

I wanted to self manage, and hence was thinking of focusing on the areas close to where we live.

House hacking will also give you some personal "property management" experience.

Learning to manage tenants, property managers, and projects is a whole other set of skills.

Biggest suggestion would be to make sure you are flexible, willing to work with multiple housing programs, and hire a good manager if you are not going to self manage the units.

Assemble a team of individuals who can split following responsibilities: contribute the earnest deposit money, guarantee the loan, find the deal/conduct the diligence, raise the capital and manage the building.

It's a good idea to talk to legal and financial experts about taxes, insurance, liability, rental agreements, and managing your finances.

He replied, "I don't know how you keep finding sellers willing to do that".Here is the secret sauce, know and understand the seller's motivation, ask questions, and don't be afraid to ask for the terms you want.It is more common in medium-sized multifamily where it is a business but not large enough to be professionally managed.

I got it under contract, she secured private funding and I managed the rehab.  

For these elusive big fish, I'd drive out to the property and talk to whoever's managing it.