Two slightly different groups of guys run into the dumpster in the mall garage when chasing Billie Jean.
The license plate on the Mercedes at the country club is the same as the plate shown in the close up bumper shot of a different car a few minutes later.
Ringwald's hand reaches into the frame toward the little boy, who is handing over the paper sack that contains a VHS tape from Billie Jean. But Ringwald is still standing by the window, snacking.
When Bynx and Lloyd are walking in the lot by the beach, and Bynx holds the gun towards Hubie, the closeup shot of Bynx's clothes are just a t-shirt when actually he has a dress over it.
(At about 1h 29 mins) Near the end Billie Jean tries to rip a poster in half, but it rips at an angle and basically just tears off a big chunk of the top corner. A few minutes later, when Lloyd picks up the pieces to throw on the fire, the poster is perfectly ripped in half.
The GI Joe walkie-talkies' range would not have been able to reach from inside the middle of mall all the way out to the outside parking garage.
At the end of the movie when the ambulance goes screaming by the surf shop, the movie makes it look like the beach is in the back yard of the surf shop because everyone is running along side and chasing the ambulance. It actually isn't. The surf shop (actually called Dockside Surf Shop) is in Flour Bluff about 5 to 7 miles from Bob Hall Pier on Padre Island where the big last beach scene was filmed.
When Billie Jean turns the TV channel and the movie Saint Joan appears, the TV is on channel 5. Whenever it's shown again on screen, it's on channel 6. Channel 6 is an actual TV station, KRIS-TV, and is the local NBC affiliate in Corpus Christi.
When riding in a car the radio station claims it is C101 but the dial shows 95.5. They may have well been listening to top 40 station, Z95 KZFM, during the filming of this scene. C101 & Z95 are still "on the air" in Corpus.
(at around 43 mins) After they've all enter the mansion and met Lloyd, Lloyd goes to the window with a candle and then jumps out, after which they see him in the pool. However, after he jumped out you can see his jacket as he's crouching down just outside the window.
When they put on another wheel after it's shot out on the station wagon the lug nuts are torqued while the car is still jacked up with almost no resistance. The tire should have been on the ground. Those lug nuts would be too loose.
When the truck rolls after shooting the tire of Ophelia's station wagon, there is only one person in the truck's cab, rather than the man and girl who were there previously. A second later, when the truck lands on its roof, the cab is empty.
When Billie Jean comes home from the police station and finds her brother's scooter heavily damaged in front of her trailer and finds Binx almost beaten to death. Billie Jean should've reported it to the police and Hubie Pyatt would've been arrested for grand theft auto and damage and assault and Billie Jean wouldn't have to become a fugitive for a crime she didn't commit.
When Billie Jean is running from the security at the golf course she gets picked up in the blue Pontiac. After the car drives away the boom mic is visible on the passenger side.
The majority of characters are depicted to have heavy southern accents. However, in the South Texas region where Corpus Christi is located, not many residents have an accent.