Factual error: Mahony gets Can$15,000 from the bank he works in in Canada and flies to Atlantic City (US) where the cashier gives him US$15,000 of chips. US and Canadian dollars are not equivalent and, at the end of 1981, the cashier should be giving him less than US$13,000. Since he is broke, he couldn't have made up the difference himself.
Factual error: Early on Mahoney is sitting in his car in the garage of Toronto Terminal 1. The time frame is 1980. There's a view of planes on taxiway and runway, it shows Canadair regional jets and Airbus A320's. Two planes that had not been invented in 1980. Not a big deal, but not historically correct.