You seem determined to attempt to find a way to DIY this... 

@Emil Pinlac I would suggest taking the @Christian Rozo approach and attempt to house hack, lenders punch your info into the system and spit out a pre qualification if you have all your ducks in a row you should get an answer in 24-48 hours.I flipped and sold a duplex here in Sacramento for 285k the property manager rented each side out for $1200.

I continue to monitor the area of Kensington Ave/E Somerset St as new houses are going up right there attempting to ride the Fishtown wave.  

The good news is that you now attempt to move into the bottom non-paying unit instead of the top.

how much reserve in percent should I think about and what things should I have in place before my first attempt at an offer?

I am attempting to go from analysis paralysis to action.My primary residence was purchased through conventional 30 yr fixed rate mortgage at 3.875% and presently have approximately 100k-130k of equity in the house.Option 1: Take heloc in equity of 100k on primary residence to complete a brrrr on a small multi family.

I've seen them created by a son attempting to convey a father's property, a wife forging her ex husbands signature and a sister forging a deceased mother's signature to defraud her brothers and sisters.Third, there's a lot of worthless property on county tax roles in this country. 

for the past 15 years, every time one of my houses becomes vacant I have ATTEMPTED to save money and rent it myself. 

Don't wait for them to attempt to get their financial lives together.

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