Compare that to putting in 100k (out of pocket) and you get a 7% return.I'm looking for advice on whether or not this is a good idea, pros and cons.

@Shawn Clark1-4 unit properties are valued using recent sales of comparable properties.

Zillow is clueless with duplex.The upper cap is SFH but how lower should a duplex be when comparing with a comparable specs SFH?

I pay interest on the money while it's in use, secure it with a note and deed of trust on the property, and then split the profit's 50/50 or in proportion to the amount of the investment compared to the total cost. 

Wait for traditional financing. ( end of 2019 - would force me to rent too long )4.

Traditional homeowners may not like it. 

Given what you have said you want to do, this is how I would do it.1) Have one couple by the property with a traditional mortgage. 

So, we are really just comparing profit options.It would take you 40 months to make up $131K with $3,200 in rental rate, just figuring the rental rate alone without expenses and mortgage payment. 

Thanks for the comment though.What I'm getting at is that comparing two scenarios....#1 I'm at a $200k property value with a $160k balance#2 I'm at a $200k property value with a $60k balance on 1st note and $80k balance on HELOC. 

I refused to replace the system plus, for whatever reason, those systems seem to be much more expensive in my area compared to what I hear for other areas.