A year ago, Norma Sanchez and Ambrocio Carrera were on the verge of losing their East Oakland home — staring down a massive rent hike and with no hope of affording a new place close to their jobs or their three sons’ schools. Now, thanks to an innovative strategy gaining traction in the Bay Area, not only did the family stay put, they’re on their way to owning that home. “It’s very emotional,” Carrera said in Spanish. “It’s something that, in the beginning, you don’t believe. But here we are.”