John Ivanoff , a 22-year-old architecture student at the Pratt Institute in Brooklyn , who shares the 1,500-square-foot apartment on Taaffe Place with five others -- the person with the only room with a real window pays an extra $ 50 in rent -- said he and his roommates and Mr. Freeman , a friend , had stayed up drinking and suddenly decided to stuff a spare mattress into the rectangular hole cut into the wall above one bedroom door . ''