When George went back for the briefcase it had no damage to it until he got it to Jerry's apartment.
When George is showing Jerry his meeting room mock-up and Jerry picks up the yellow M&M, he's holding it differently in the close-up and the long shot. His fingers are in different positions.
At 17:14 when Jerry picks up the M&M figurine (which should be George!!), his hand is holding it from above. On the close-up, his hand is holding it from behind.
When Jerry is chasing Newman throughout the apartment building and finally catches him, Newman's back is against apartment door 4D. When the camera angle changes over Jerry's shoulder apartment door 5E can be seen. Since the number refers to the floor the room is on, 4D and 5E should not be visible from each other.
Jerry (Jerry Seinfeld) and George (Jason Alexander) spend a lengthy period of time waiting while the tape is rewound, but later it's revealed that the recorder was shut off after only recording approx. five seconds of audio.
At 2:51 when Jerry and George are walking down the street, Jerry inadvertently opens his red jacket - revealing a microphone wire taped to his shirt.
Kevin (Tim DeKay) claims to have a jet ski kept in his garage but in a later episode we learn he lives in an apartment & doesn't have a garage.