I got a call from 415-376-4796 "privacy" after getting another "Privacy" call a few days before from 415-704-1785. In searching on the web I find that although these are supposedly San Francisco numbers they both have links to second rate phone services with in Oakland. I suspect these are organized crime scammers who call with automated equipment and a variety of ever changing numbers (I have about 25 of them). They take numbers which are from closed businesses and somehow get control of them and use them for a Florida or Caribbean vacation scam. This has been going on for years. With call blocking equipment they change their numbers monthly to get past the blockers. They usually call on a Tuesday midday to set up their dialer then back on another yet number. The feds need to look into this scam it is major and long term with sophisticated resources and operated out of Oakland...
I suspect they got my number years ago from a false craigslist focus group ad or from a mole in a legitimate market research company in the bay area...