Median income is not a strong fundamental in SF.  

I would suggest building a strong team around you for your first few investments to help you get some skin in the game.

Being conservative is probably key seeing as you're not here and there are so many unknowns to deal with (you're probably not going to want to do anything opportunistic where you meed value add straight away unless you have a strong personal connection to a contractor here - we can probably help there, but obviously that's your call).

Definitely check into some local REIA meet ups in your area, and network to build a strong team around you for your first couple of investments.

I suggest building a strong team around you (broker, mentor, lender, etc) for your first investment at least to help you gain experience.

If your reason why isn't strong, you'll give up.A huge way to combat discouragement is to listen to the podcasts, read the blogs, and interact here on the forums.

Look into an FHA loan as an owner occupied building has strong financing options. 

Make sure you start with some strong contenders.

I'd suggest building a strong relationship with an agent who can give you proper after repair values as well as understanding if homes are moving in the market.

On the wholesale side it sounds like a lot of work for less than $1k.Correct me if I'm wrong, but I believe owner occupants get first look on HUD properties and are allowed to finance them.I would strongly suggest taking 5 or 10k of that 20 and doing a targeted direct mail campaign.