Dueling Shows: With The Price Is Right, to an extent. Deal had games in which contestants had to guess the prices of grocery items. When Price returned to the air in 1972, it was reformulated to include similar games. Mostly averted now as both shows appear on the same network, although Deal no longer has the pricing deals (according to Mike Richards, to avoid being too similar to Price...despite the fact he spearheads both).
Franchise Killer: Outright averted with not only the 1990 revival, but also FOX's Big Deal (1996) and the 2003 revival for NBC. The former was hosted by the inexperienced Bob Hilton, and failed so badly that Hall returned to host the tail end of it in an attempt at an Author's Saving Throw. The latter two lasted six and three episodes, respectively, these revivals had obviously transparent attempts at being "hip" and "edgy". The fact that the Brady version began its seventh season in 2015 shows that the three revivals before it were not detrimental.
In Memoriam: The October 6, 2017 episode of the current version featured a special tribute to Monty Hall, who had died September 30.
The original NBC era (1963-68) appears to be mostly gone. The 1963 pilot was aired by GSN as a standalone special in 2003, and also shown by Buzzr several times. One episode from 1965 and two from 1967 are held by the Paley Center for Media, while a few silent color clips of a 1966 episode surfaced in May 2013.
The 1968-76 ABC daytime series has a few episodes around: three episodes from 1969, a master copy of a 1974 show (posted by a relative of one of the contestants), and an audio recording of the 1976 finale. An excerpt of an episode with substitute Dennis James was included on the 1972 pitch film for The New Price Is Right.
The 1969-71 ABC primetime version has four episodes known to circulate: two from 1970 which were put into the package for the first syndicated season, one from 1971 which was also put into said package (all three were eventually reaired by GSN and Buzzr), and the 1969 debut (aired by Buzzr as part of a special "Lost and Found" week in September 2015).
The 1980-81 series is also pretty rare, with only three episodes known to circulate and a fourth (#C-82, taped 11/30/80) held by UCLA. Two of the circulating episodes (one with a $5,863 Big Deal, the other with a $4,235 one) have an intro consisting of clips from the 1970s, including a $29,795 Super Deal win; the third, with a $4,187 Big Deal, has an intro consisting of clips from this version.
The 1984-86 version has been rerun on the USA Network, The Family Channel and GSN, although the latter never aired any Season 2 episodes. Buzzr has started to run the show beginning on June 1, 2016.
The 1990-2003 versions haven't been in reruns at all.
Long-Runners: The original series was in production from 1963-77.
Milestone Celebration: The show celebrated its 50th Anniversary (albeit months ahead of the actual anniversary on 12/30/13, and slightly ahead of the anniversary of the pilot's recording on 5/25/13) with a two-week stretch between February 18-March 3, 2013 with deals integrating elements from the 1963-77 run (but still no pricing), the return of the $50,000 Super Deal, and the March 1 show featured a deal done by Monty and Carol Merrill.
Never Work with Children or Animals: For the most part, the animals - many of them came from local zoos - cooperated well with Monty, the models and announcers, and others who worked with them. But there were times where someone listening real close could immediately sense a Zonk was hiding behind the curtain, just by hearing a honk, growl, bark, etc. At least once, a bear was behind one of the Curtains and he decided to growl real loud ... just as a trader was making up her mind; she immediately took the cash buyout that Hall had offered her.
Recycled Soundtrack: Several 1980s episodes recycled part of the 70s theme to another Hatos-Hall series, Split Second, mainly for cars; for the same purpose, the themes to the short-lived Hatos-Hall games 3 for the Money and It's Anybody's Guess were also reused.
In mid-1967, NBC put a nighttime version of Deal on as a Summer replacement. The show did extremely well, beating its competition to a pulp, leading to Monty approaching the network about putting it on the regular schedule. NBC balked, leading to Hall wanting to move the show elsewhere.
The ABC daytime version was screwed by the network's attempts to boost ratings by having the show offer huge prizes and go to an hour-long format. When this failed, the show was moved on December 29, 1975 from 1:00 PM to Noon — against High Rollers on NBC and local programming on CBS. Despite initial success (forcing Rollers to 10:30 AM and defeating its replacement, the return of The Magnificent Marble Machine), Deal fell on July 9, 1976 against The Fun Factory.
The 1990s version was originally hosted by Bob Hilton. Hall replaced him as "guest host" in October, with the intention of eventually doing a series of on-air auditions, then picking one of the candidates to host the show on a permanent basis. NBC had other plans (namely, Wheel of Fortune), and canned the show outright.
Big Deal had far too many things going against it to list here, the least of which was being slotted right after NFL games...which tend to go overtime. For East Coast viewers the problem was so bad that, out of six episodes, only three aired in full!
The 2003 run had an unproven host in Billy Bush and several skits that smacked too hard of trying to be "hip" and "modern". Then, on the last aired episode, a one-deal appearance by the Big Dealer himself made Bush look like a total imbecile. note (Nothing against Bush or any other host, though — Hall was just that good at making a very complicated job look easy.)
Talking to Himself: In the two deals below, Dean Goss is hosting and announcing at the same time, but according to the comments his announcing was pre-taped.
During his year as announcer, Goss hosted twodeals with Monty appearing in a cameo. Goss said in a later interview that these deals were done on purpose — Monty wanted to leave the show, and so tested his announcer's hosting abilities. Had that version been renewed for Season 3, Monty would've passed the torch to him on the season premiere.
According to Goss himself, he had beat out Phil Hartman for the announcer/sidekick role, and the reason Season 3 didn't happen was because Telepictures thought it'd be too hard of a sell without Monty.
When Monty Hall originally approached Telepictures about doing a show for them, he originally wanted to do a talk show, but when Telepictures realized they had Monty Hall working for them, they just decided to revive Deal - not that Monty minded.
As noted above, Monty's plans for the early-1990s version, which were scuttled by NBC.
Shortly after Big Deal's six episodes had aired, there were talks of bringing it back in March 1997. The new episodes would've been a half-hour long, and Mark DeCarlo would have had a female co-host. This didn't fly, and the first six episodes became the only six episodes.
Gordon Elliott hosted a pilot for the 1998-99 syndication season produced by Buena Vista TV (Disney) that appeared to stay closer to the traditional format, but it was never picked up - possibly because of the fear of a repeat of Big Deal (the fact that Stone-Stanley Entertainment, which co-produced Big Deal, also co-produced this pilot probably didn't help matters).