Plot hole: At the end of the film Mardukas reveals that he has been wearing a body belt packed with cash - "in the neighbourhood of three hundred thousand dollars" - ever since Jack detained him in New York. Are we to assume that Jack Walsh, an experienced, hard-bitten ex-police officer, now a bounty hunter who routinely chases down violent and armed bail absconders who would kill him without a second thought, didn't even perform a perfunctory search of Mardukas when he detained him? This man used to work for the Mafia! What if he was carrying a weapon? A body belt with three hundred one thousand dollar bills in it would be uncovered by even the most casual pat down.
Continuity mistake: At the beginning of the movie when Tony and Joey (Morons #1 and 2) meet Jack Walsh at the car rental desk, Tony writes a phone number on a packet of matches in pencil. Near the end of the movie when Jack Walsh fishes this pack of matches from his pocket, the phone number is written in pen.