Architecture did a design and well respected contractor estimated the buildout of 4 plex would be an additional ~800k for total project cost of ~1M. it would be ~1.2M for the 7 plex.  

You are correct, that this has long been the conventional figure used to estimate cost for buildable sf in NYC. 

About 20% use DSCR (usually 20-25% down) and the rest are cash or hard money or something else.For $325k purchase:1) As a broker I would negotiate down as its been on the market a while and its especially now in holidays)2) I would also negotiate seller paid closing cost credits, most loans allow 3% which should cover most or all of that.3) Assuming you paid $325k but got closing costs covered I would anticipate a minimum of $32,500 down and maximum $65,000 down depending on lending product chosen.4) Remember you still must furnish and I use $20/ft as a safe estimate to fully outfit an STR property.Best of luck!

Quote from @Travis Timmons: @Jay Hinrichs this is an educated guess, but I think the market rent for our property unfurnished, long term would be approximately $1100 per month and we have rented it for $1600 per month as a furnished, medium term rental.  

Please also make sure how much points or cost you are paying by looking at the Loan Estimate.

I was holding approximately 20 of their properties at that time, so you can imagine that unexpectedly paying out 20 interest payments every month was impossible.   

Estimated about $25,000 including utility hookups.  

Please also make sure how much points or cost you are paying by looking at the Loan Estimate.

Depending on your estimate of the ARV and the ability to raise the rent on the 1BR, this looks like a "lendable" deal, IMO. 

.: I would personally ask for a price decrease based on whatever estimate they got for the installation of that equipment (assuming you can get a loan without those things - depends big time on the bank - my local banks would do it for me).