 The vault which James Caans character breaks into in the opening  scene was a real vault, purchased at a cost of $10,000, specifically  so that Caan could break into it, using the tools and techniques  supplied by John Santucci. Every crew member was armed with a fire  extinguisher in case of a blaze from the intense heat of the thermal  lance. Caan later remarked that although many elements of John  Santucci found their way into the character of Frank, he resisted  doing a straight impersonation of the boisterous Santucci.