I am looking at mid to upper range SF.

I made lots of mistakes, but with those mistakes came lessons and learning opportunities.For my next investment I particularly plan to look into buying another fixer upper or a duplex, not quite BRRRR yet.

But your PITI is probably in the low $400 or upper $300, then budgeting $150/month for maintenance and capex, and renting for $750, and then you’re left with your $200 cash flow.

This property is in an upper-middle class neighborhood.

The upper middle class supports CA. 

Think the QI controls the up-leg until you sell the down-leg.LESSON - BEFORE you do any transaction, get with someone that knows what they're doing like a QIThen again, I see these <1% of the time, since most people need to sell something first to pay for the replacement.

I am trying to buy my first property and found a fixer upper with the opportunity to add a unit in the bottom basement.

Maybe if you find a real fixer-upper that none of the non-investment buyers want to touch you could find something that makes sense, but then you'll probably be competing with the flippers.

Not really wanting to house hack in a du/tri/quad but we are wanting to buy a fixer upper home with an existing detached ADU that we can rehab into a short term rental property. 

When I first started investing, I was telling everybody that I was looking for a cheap fixer upper.