How to estimate cost to build multifamily in NYC?

[Amit Gera]

BP Newbie here looking to get some help or direction on how to properly estimate out the average cost to build an 8 unit condo building in Brooklyn, NYC. I've been an investor and fix-and-flipper in NY for 4 years now, with 20+ projects under my belt, but this will be my first ground-up multifamily development project.

Essentially I'm purchasing a 2 family property that is zoned and sized to be able to build out a 4 story 8-unit structure. Based on area comps, I'm purchasing below market value. Currently on the block, there are 2 projects of the same nature in various phases of construction (both are beyond the midway point of nearing completion).

I'm at the point now where I need some assistance in how to estimate the cost to build the 8 unit condo that I intend on building, should numbers make sense. Otherwise I have the option of renovating the existing property as well. I plan on purchasing the property cash (I have the liquidity available), but should I go the route of doing the condo development, I would need to get a development and construction loan.

I would also certainly be open to suggestions and referrals for architects, attorneys, lenders, contractors etc. if anyone is willing to do so.

Looking forward to being a part of this community!