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

I had my husband request membership to see if he can message the admin the correct information in that group.  

It seems great on paper because you were technically creating more income but you are also creating more of a headache...Cramming in bedrooms and forcing living space is not always the best way of going about things.

The remaining lone balance for house a is $117k, correct

To the other experienced investors out there am I analyzing this correctly?

correct and at new rates

mario,  correct on the math.Now for sure you need to rehab it.

Most fail to paper the contracts, indemnification and additional insured requirements correctly.

You are probably correct.  

. - of course, your conclusion is correct.