The predicament is all too familiar to students hunting for college bargains. Focused on cost, they attend the institution that showers them with the most money. But many learn a bitter economic lesson once they enroll: The debt can mount during the course of an undergraduate career, thanks to fine print, tough academic requirements on grants, and unanticipated tuition and fee increases. Few tools or resources forecast anything about the costs of sophomore, junior or senior year, and there’s little information available about how financial aid changes for upperclassmen.