Roomate Shares (San Francisco, Pasadena: apartment, rental, house)

[Laocoön]

Regarding Roommate Shares:

Anybody out there have any experience sharing a rental house or apartment with roommates you didn't personally know? In other words, have you answered an classified ad of "roommate wanted" and eventually moved in with an unknown person or two, or three?

For those who have done this, what screening process would you recommend for the guy moving in? Specifically. (Obviously there will be a checks run on the prospective tenet by the current main resident(s) and/or the landlord.)

What are some red flags to look for during the initial meeting and walk-through? What questions could you get out of the way over the phone that might help pre-screen the situation before the prospective instigates the face-to-face interview, walk-through, and formal application process?

I am considering going the roommate share route in California, in whichever destination I finally decide to land in, either the San Francisco Bay Area (the peninsula, Marin County, or possibly the city), the West side of L.A., or perhaps Pasadena. This will happen by mid-summer.

I'm all ears. Lend me your words of wisdom.