The vault which Frank breaks into in the opening scene was a real vault, purchased at a cost of $10,000, specifically so that James Caan could break into it, using the tools and techniques supplied by John Santucci.
The burglary tools used throughout the film (such as the hydraulic drill used in the opening sequence) were not props, but actual tools which the actors were trained to use. The tools were supplied by actual thieves who served as technical consultants on the film, principally John Santucci, who also portrays Sgt. Urizzi on screen.
The screenplay for this film was adapted from the novel "The Home Invaders", written by Frank Hohimer, himself a professional thief. Hohimer was serving time in prison at the time this film was in production.
When Frank tries to light his cigarette in the diner scene, the lighter does not work. This was not scripted. The prison story that Frank tells in his monologue is based on a letter Michael Mann received from a real inmate.
According to James Caan on the DVD commentary, Frank is based on John Santucci. But Caan avoided doing an impersonation of Santucci's exuberant personality because he felt that it would seem too comedic.
The house that was "severely damage" in the explosion was demolished and three smaller homes were built on the property. Apparently the explosive charge was too large for the job as it caused a fire and cracked the home's foundation.
Dennis Farina was a Chicago policeman at the time of filming. He plays a henchman. Conversley, John Santucci, who plays a corrupt cop, was a recently paroled thief and acted as a technical adviser. They were both cast in Michael Mann's TV series Crime Story (1986), Farina as a Chicago police lieutenant and Santucci as a jewel thief. William Petersen, who later would star (along with Farina) in Mann's Manhunter (1986), appears briefly as a bouncer at a club.
Michael Mann: [Cops & Robbers] Many real-life Chicago criminals and police officers served as advisors to director Michael Mann, and Mann cast many of them on screen, often in contradictory roles (i.e. former Chicago police officers Dennis Farina and Nick Nickeas appear as criminal henchmen, while former professional thief John Santucci appears as a police officer).
The house that was blown up was actually a fake structure in front of the real house; nevertheless, when it blew up it heavily damaged the real house behind it. The residents and neighbors were moved to a hotel during filming.