was it possible that the killer lived in the auburn manor apartments?the decision was made by the supervisors to send those keys out with teams of detectives to see, or at least rule out, if those keys went to any of the apartment buildings. >> rockford police. >> investigators tried the keys in dozens of apartment doors, a tedious, time-consuming process, with no success. >> the apartment complex, i think it's four or five buildings or six buildings, you know, there's a lot of apartments. that's why they set out with four sets of keys and teams of detectives. >> they were beginning to wonder whether this was a dead end until they got to the bottom floor, and finally got a hit. >> they were surprised, you know, to the point they were saying, oh, my god, you know, this key works at this particular apartment here. >> the man inside the apartment was 46-year-old calvin powell, and he was well known to police. >> he's a colorful character. he's got several minor arrests, i believe there are some felonies for drugs or for, you know, property crimes. >> powel