Quote from @Eric Prescott: Yes, I understand that appreciation often means less cash flow and good cash flow typically means weaker appreciation, but there is a sweet spot where there is decent appreciation and sufficient cash flow to cover expenses so that the property pays for itself, and that is what I'm honing in on. 

.• Sales Recency: Did any of the comparable sales close more than three months ago?

I recently purchased a three family with a 50% finished basement that currently is only used for laundry.

Well....should you invest in a city where the people elected a woman with foreclosures, liens, judgements, garnishments, ethical violations from the state ethics board,  misused a city credit card, went three years arrears on her federal taxes all while yelling for other people to pay "  their fair share, " left skeletonized dead bodies hanging over Canal St for months on end covered only by a tarp until the wind blew it off to reveal to our horror her blatant disrespect for human dignity?

I always used your number three as my prime focus when I started doing short-term rentals twenty years ago, before Airbnb existed.

I went to a three day boot camp and the stuff that was presented did not have the nuts and bolts to go with it. 

I’ve been working with a bank’s agent over the past three months on a single-family home listing in my area.

We are looking at investment properties in Brooklyn, and found one we liked and want to add an additional floor (two stories as of now, would go to three), but the zoning is M1-2, which is commercial.  90% of surrounding properties are multifamily residential as well.

I was just wondering if that was sufficient.

That's three hours out of that manager's day, plus gas.