I'm asking anybody with experience in new construction what a ball park price for a single story 3 bedroom 2 bath home would be?

Two years ago I quit my Job in which I worked for 11 years, I invested most of my savings in Single Family Houses, buy, fix and rent and so far is going good.

i want to end up in multi family homes in the long run, but i have no money down, no money for vacancy,repairs,rehab, etc.. my idea was to start with a single family home(easier) with good equity, live in it. but fix it up a little & house hack to pay my mortgage. then a year or two down the road pull out the equity or even sell and purchase a multi family home that way ill have more money to back me up. how does that sound as a first investment? 

The preliminary information I have about the potential seller is that they're seeking to reinvest in a different locale, so looking to dump all properties in location A to reinvest in location B.Some questions I have:Big bank vs small[er] bank vs private lender - who, if any, would be most inclined to view this as a basket for a single mortgage?

I also used a HELOC to buy my first single family several years ago. 

Purchase price: $260 Bought my first single family home 3bed 2 bath.

Purchase price: $340,000 Our 5th unit, single family home zoned for secondary suite.I will be covering this unit into an up and down duplex.

All older folks and a 1970s single story building.

Please let me know if I'm not including any expenses or missing something key.Property Details:- 3 / 2, 1374 sqft, $89k askingExpenses ($802)P&I: $369Tax: $188Insurance: $70Utilities: $50Vacancy: 5% ($62.50)CapEx: 5% ($62.50)Total Investment (Down Payment + Closing + Repair) = $25,499Rent = $1250Cash Flow = $448Cash On Cash ROI = 21.08%This is a single family home in an area where I've competitively estimated the rent (Most units running between $1150 and $1450). 

If you are looking to flip a duplex while house hacking it, it’s not going to get as much interest and, aruably, appreciation as a single family home.