I experienced not one, but two predatory student-rental and hotel markets regarding our daughter within the past few years: Philly (twice, in 2006-7, and 2009-11), and Boston (2008-9). The number of students in each is staggering, and nearly all of them graduate within the same two-week period each year. (Sorry, but I'm not up to speed regarding current estimates of the number of degree-granting institutions and the total number of students in each metropolitan area. When I was a graduate student in Boston in the 1970s, there were ~ 250,000 students attending 67 colleges and universities there.)