What does Elvis find when he goes to Pritzk's apartment?

When Elvis goes to Steve Pritzik's apartment, he meets a neighbor who informs Cole that a man named Elton lives in the apartment. She tells Elvis that Elton has not lived in the apartment in several months, again fitting the Susan Martin murder time line. Cole enters the apartment and finds it a mess, with the utilities cut off. Elvis checks the bedrooms but does not find anything. He goes back into the living room and finds a manila envelope behind a couch cushion. It is addressed to Elton Richards and has been opened and resealed. Inside are pictures of Susan and Teddy Martin, and a map of a floor plan of a large house. Elvis determines they are maps of Teddy Martin's house and neighborhood.