During the Money Cards, a "double" (or having the next card be the same value as the previous one) used to lose the contestant money. Enough contestants cried foul, and eventually it became a push in 1981.
When it premiered on the CBS version, contestants had won $90,000 in 1 week on the Money Cards. The producers realized that the original change card rules produced too many big wins. To control the prize budget, the rules reinstated to changing 1 card, per line.
Two $500 bonuses were added to the main game by 1981. One for if a contestant hits the actual number in a question right on, and one for if a contestant can run his line of cards to the end without freezing or guessing wrong.
From it's debut until June 20th 1980, the show aired at 10:00 am on NBC. After a schedule shuffle at NBC to accommodate The David Letterman Show (1980), Card Sharks was moved to noon where it faced fierce competition against top-rated game show Family Feud (1976) on ABC and the first half of The Young and the Restless (1973) in certain markets on CBS.
On the original Jim Perry version, each time a player freezes their own position, the player's freeze bar electronically moved by itself. On the Bob Eubanks/Bill Rafferty reboot, the freeze bar was moved manually by the models.
On the CBS version, when a contestant won a car, the word "CAR" circling around the winner appears to be a rainbow color scheme, would also be shown around the contestant (similar to the graphic of chasing rainbow cars on Classic Concentration (1987)). Though for the first few weeks, it didn't appear, until November 1986. The most coincidental thing is both game shows were produced by Mark Goodson, they both aired, at the same time, but on different networks.
Just like the NBC version, whenever there was a tiebreaker, the CBS version would also have 3 cards, along with 3 questions. This changed on February 29, 1988 until the series' ending, the tiebreaker is changed to only a 1 question sudden death game; where both base cards are shown before the winner of the question decides whether they needed to play or pass.
When the second version (CBS) was in development, former host Jim Perry was Mark Goodson's first choice, a second time, when he was already under contract with NBC, who was also hosting Sale of the Century (1983) at the time, therefore, the job was given to Bob Eubanks, who previously hosted the short-lived Goodson game show Trivia Trap (1984), who was also hosting The New Newlywed Game (1984) at the time.
It premiered on January 6, 1986, on CBS at 10:30 A.M. EST/9:30 PST, replacing Body Language (1984), whose network also relocated Press Your Luck (1983), in the time slot of 4:00 P.M. EST/3:00 P.M. PST.
On the CBS version, like The Price Is Right (1972), earlier in the run, before a commercial break, director Marc Breslow would do a freeze frame of the winning contestant, who played The Big Money Cards.
During the CBS series, over 6,000 questions were asked, including roughly over 1,500 audience polling questions, roughly over 600 educated guess questions, and over 4,000 questions asked of 100 individuals. Some of the questions were recycled in later episodes, but educated guess questions were very rarely recycled.
When the show returned to CBS, and after the Money Cards, contestants did not play for a car. On October 27, 1986, for the CBS version, a winning contestant received one Joker for winning the match. Three more were added to the Money Cards deck, and if a contestant uncovered them they received an additional chance to win the car. After the Money Cards round was over, a row of seven numbered cards was wheeled out, in front of them and the contestant placed whatever Jokers they'd earned over the cards in the hopes that behind one of them was the word "CAR". During the special weeks when children played, the top prize was a trip to Hawaii (with either "WIN" or "HAWAII" displayed on one of the cards) and the children were given two Jokers to start. From July 4, 1988 until the show's ending, the winning contestant had to correctly predict one final audience poll question. To record their guess, the contestant used a special prop with a dial and the numbers 0 through 10 on it. The contestant moved the dial to the number they thought was correct, and if it was they won the car. Missing by one in either direction won the contestant $500 as a consolation prize, while any other incorrect guess won nothing. On the final episode, however, if the contestant was even one off, they still won the car. This version of the car game was based on the "Judge the Jury" round on the short-lived Goodson game show, Mindreaders (1979).