In a move that echoes Warren Buffett's value investing principles, Ian Jacobs is making a contrarian bet on San Francisco’s beleaguered downtown real-estate market. Jacobs, who cut his teeth in the world of high-stakes investing by once seeking an apprenticeship with the legendary Buffett, is no stranger to going against the grain. “He wrote Warren a letter that said, ‘You're my role model and I'd like to make you a value proposition — I'll pay you $500 a week for the opportunity to intern for y