Apollonia's application card says she is at the Royal Hotel. Later in the film, when Prince reads the card, which is pinned to the notice board, her address is the Huntington Hotel, the handwriting is completely different, and the notice board pin is in a different position. When The Kid then walks away from the notice board, the card is one seen earlier.
When Morris sits down with Apollonia and asks Jerome to ask the waitress to bring a bottle of her best champagne scene. He tells Apollonia in his bed room he has a brass water bed. Apollonia appears to giggle. But the sound of giggling must have been edited in. She appears to just be smiling. And it happens again after Morris is talking about his chef Geno Satascratchy or something.
When Apollonia fills out the note card, she lists her height as 5'7". The following day, a closeup of the card shows her height as 5'6".
The note card application Apollonia fills out in the first club scene lists her experience as "Singer & Dancer." When it's posted on the board in later scenes, that section is blank.
In the Lake Minnetonka scene, after Apollonia starts to get dressed after getting wet, her makeup is perfect. When she gets back on Prince's motorcycle, he says "don't get my seat all wet". She kisses him, and before they ride off her hair is wet and unstyled. In the next shot, filmed from behind, her hair is totally dry and styled.
When Jerome and Morris are walking around the block, discussing the problems with the girls' group, Morris says "That Apollonia babe we saw last night," and his lips don't move in sync with the dialogue. He's actually mouthing "Vanity" instead of "Apollonia", indicating that the scene was filmed before Vanity backed out of the shoot.
Morris and Apollonia's conversation in the car outside of the club is dubbed over Morris talking to Jerome.
After The Kid hits Apollonia in the face, she cries. The dialogue overdubs "Just leave me alone" while she is clearly still crying.
During the "Let's Go Crazy" sequence, when Morris examines himself in a mirror, he takes a step to the side, revealing a stage hand in a white cap in the mirror. He realizes he's in the shot and takes a step to the side.
The Kid's motorcycle has an automatic transmission. Sometimes when The Kid does crazy bike tricks, the clutch is visible, indicating a stunt rider on a manual bike.
When Apollonia follows The Kid through the mall after he gets her anklet, a white flash is visible, presumably the publicists taking production photos.
At the end of "When Doves Cry", a palm tree is visible in the background as Prince drives up his street. The film is set in Minneapolis.
When Apollonia says "I'm thinking about buying a guitar", the boom mic is visible.