Continuity mistake: At the end of the movie, Jack parks the car in front of a palm tree and walks onto the beach. The shot changes while he stands there for a few minutes. As the shot changes back to show him walking off the beach, the car is no longer in front of the tree, nor does he drive by during the credits. I hope he enjoys his walk back to Miami.
Factual error: When Robert Redford looks at the radio he finds in Lena Olin's car, the radio's ID plate has a serial number beginning with 67-, which means it was paid for by the U.S. government with funds from fiscal year 1967 - eight years too new for a story from late 1958.
Plot hole: Roberta asks Jack to drive her car from the port to the casino to smuggle a transmitter through the checkposts. Since her links to the revolution were known to the authorities, and the chances that her car would be checked were much higher than with Jack's (which eventually also happened) it would have made much more sense if he had transported the transmitter in his own car.