I have also seen appraisers recognize that multiple ADUs by rule does not qualify for conventional F/f financing.  

Conventional Financing How did you add value to the deal?

I am based in Seattle, but is licensed in Tx.You can acquire your a primary residence from up to 1-4 units for as low as 5% with conventional or 3.5% with FHA with a few exceptions.

If they want their money back fast like a flip then let them flip it and you buy it as a primary residence with a conventional or fha mortgage.

9) adding multiple ADUs or adding an ADU to a quad looses F/F conventional financing.

Take that money (it's all tax free) and use some to buy a small multi-family using conventional or FHA financing. 

I'm feeling most drawn to a buy and hold rental investing strategy and like the idea of the BRRRR strategy in tandem with VA loans, basically refinancing VA loan backed mortgages to conventional loans once there is 20% equity in the home.

Our entire network of agents, title companies, insurance, conventional lenders, private lenders, and many others come together to make this an enjoyable experience.

If you aren't paying cash and are doing owner occupancy you may be able to use FHA instead of Conventional with a higher down payment. 

You just have to make sure you're using someone that actually knows what they are doing and not someone that throws it to a lender that specializes in Conventional Loans.