Here\'s my attempt to break this down:
Even though the limit for 7 days seems to be the case for many NBC shows in the late 70\'s/Early 80\'s, the shows you\'ve mentioned didn\'t have such a limit.
- Sale (earlier in \'87) allowed for a 11 games because of the Winner\'s Board, but by the end of \'87 changed to an 8-day maximum (and that\'s IF you win game 7 and it\'s Big Money Game, otherwise you go bye-bye).
- Wheel had a three-day limit since the Woolery Era.
- Scrabble at this point had a 5-day limit.
- Blockbusters had 10-game limits
- Concentration had the one-loss rule; but I\'m unsure about the maximum amount of victories (Five?)
- WLoD escapes me. The syndie rules varied from the daytime version.
- Super Password had five game limits.
Out of the maximum winnings, it would really depend what show and if there was a rollover jackpot. For example: On Sale, you had the opportunity to win over $100,000 if you won the 11-games (exception; O\'Brien, Tom). You\'re assured roughly $55K or $60K if you win 10-games (plus prizes and bargains).
Blockbusters allowed you to win 10 games. Assume 10 wins (at $200 a match), plus the $5,000 each time, you could stand to win $52,000 minimum (the rollover jackpot later) would\'ve given you the opportunity to win more than that but not by much.
Super Password would\'ve depended if the person (or people) goofed up in the bonus. So you could win $10,000 in your bonus, or only $5,000. Same with Scrabble. Your Sprint amount depended on previous attempts plus whatever bonuses you got in Crossword.
TL;DR: Sale of the Century gives you a high cashout rate.