Many people facing foreclosure have successfully made the trial mortgage modification payments required of them, but they’ve been unable to get their banks to make the modifications permanent. For example, California homeowner Marvin Galvin and family made 14 monthly trial payments to JPMorgan Chase, totaling some $30,000, before receiving notice last week that their house would be sold in foreclosure. The sale is set for Jan. 7 Here’s a closer look at their stories, which share key features, and at some of the obstacles — beyond too few competent staff at the banks — to getting successful trial modifications converted.