Does anyone have experience of setting up a STR while in the same position? 

It will probably depend on your experience and connections with lenders.

It seems like the LO's have no experience working with investors and are not very concerned with trying to make the numbers work.

I am an accredited investor, looking to invest 50k to start since it’s my first one, and predominately interested in multifamily as my only previous experience is a rental I manage on Airbnb.

They are going to finance you based on your loan to value, experience, and liquidity. 

I can see the OP giving this a shot.. but it is risky he could end up making a few bucks and getting experience might just break even or he could take a loss.. that margin is very thin in markets that are not selling as soon as you get CO  thats been one reason we have been profitable very few homes have been carried past CO so financing cost are at a minimum.. you hold a spec home 6 months past Co and every month your losing money you will not recover.

I want happy campers in my network - you've helped reiterate any deal can be good at the right purchase price.Huh, well, that is a kudos on your level of research or you've got some serious luck on your side because as chance has it I have experience working both with organizations similar to what you described and in leasing by the room. 

Any advice or shared experience would be great.

In order to get there it would be good if you could keep feeding cashflow proceeds back into acquisitions, on top of your continued W2.Speaking from experience, you can manage probably 30-50 units yourself nights and weekends before you really need to hire someone.

Rent control in the bay area can be extreme as many areas have rent control in excess of the state mandated rent controlIn general experience RE investors are not choosing to add a single ADU in single family zoned areas.