Here is a great white paper on the topic published by Old Capital:https://www.wealthgrowinvestments.com/wp-content/uploads/2017/06/Multifamily-Financing-101-FINAL-2017.pdfAnother factor is getting a sense of the market for the debt of your project.

I realize a lot of factors are at play when arriving at this number, aiming for average cost per sf in NNJ in a nice neighborhood.

Since then, there have been many other factors contributing to a deteriorating relationship between myself and my landlords.

-Are rents justifying the increase or is there a variable factor playing a significant role that I have yet to distinguish?

As @Kay Kay Singh said, there are a lot of factors to consider, but ultimately you're looking to confirm that there will be future demand for your investment and you're buying at a number where you can make desirable returns both today and in the future.We have specific metrics for our investors such as IRR, cash on cash, equity multiple, etc.

@Seth Alexander I see this is your first post so welcome to BP.How to invest depends on a lot of factors.

It needs to have credit score (if reason) or others factors (active collections, etc.) and name and contact info for the credit bureau used. 

The other factor is opportunistic price increases.

The reason no one can give you a firm amount is because PMI fluctuates according to a bunch of different factors.

Many different factors such as current expenses, condition of the property, additional revenue opportunities, surrounding neighborhood/surrounding rents.