During the chase scene, the car driven by Agent Downey and Jack Sylvester passes the Alto-Nido Apartments (1851 N. Ivar Street, Hollywood, California). In Sunset Blvd. this is the apartment building where Joe Gillis lived before he moved to Norma Desmond's mansion.
In the first scene at the hotel, the telephone rings to the tune of "Pennsylvania 6-5000", with Fejos (Michael Richards) answering the line as "Transylvania 6-5-0-0-0" to the beat of the tune.