Purchase price: $74,000 Cash invested: $25,000 Sale price: $145,000 I acquired a property from a couple needing to relocate, with significant repairs required.

So, your focus may need to pivot from high rental cash flow to little to no cash flow as a rental with an appreciation upside.I would recommend taking your $150K to $200K and securing a solid equity position in something that will cover its expenses and maybe provide a small cash flow, but then is poised to appreciate nicely over the course of the next several years. 

I currently live in it as my primary residence but had plans to eventually rent it out and then cash out refi once I reach 20% equity in the property.

This could turn a potential loss into positive cash flow while protecting your property’s value.

Apparently they take preferred interest in your company or have you sign a UCC cash flow agreement.

$400k equity is producing $1600/month cash flow for a return from the cash flow of 4.8%.  

He can't 'buy her out' as he does not have that much cash liquid.

Duplexes cash flow better, have less risk, AND EASIER TO MANAGE compared to a SFH.  

To be more specific about what i'm looking to do: My 1-2 year goal is to employ the BRRRR strategy with SFHs and Condos by buying distressed / highly undervalued properties that need work (preferably all-cash) in low crime areas with strong rental demand, renovate them within budget (again preferably all-cash) and get them rent ready before refinancing them at the highest ARV possible.

A common strategy I see with diversification exchanges, is that the investor will purchase the first property cash and the second with a mortgage.