You most definitely can go in on a Fourplex with 3.5% down, primary residence, living in one of the units, find out what purchase power you have, and what the rent rolls for the other units will be to determine your cash flow. 

Essentially rolling that equity from each property into the next one, with a cash out refinance each time? 

It will roll into the new basis of your replacement property.

MULTIFAMILY EGI INCOMEMultifamily GPR: Rent Roll Rents w/ Laggards @ MarketLess - Concessions: 0.50%-1.00% (Depending on market)Less - Vacancy: 5.00%-7.00% (Depending on market)Less - Bad Debt / Delinquency: 0.50%-1.00% (Depending on market)Multifamily NRI= Multifamily GPR - Concessions - Vacancy - Bad DebtOther Income: Get a rent roll detail showing all the other lease charges by unit.

@Bob AsadOnce under contact getting the rent rolls, maintenance, and any capital expenditures expenses.

We promise returns for our partners and worked with previous partners to put together build plans to quickly get the ball rolling with this project.

I think it would be important to look at your ROI after your move out and if its worthwhile to hold or potentially sell to roll capital into another more lucrative investment. 

I would even be content with neutral or just a small positive cash flow to get it rolling.

Hey Michael, This is a loaded question as there are a lot of variables that will play a roll into the cost.

It is hard work and takes a long time to get the ball rolling.