Other mistake: When Molly and Sam are "dancing" to the jukebox playing Unchained Melody by the Righteous Brothers, the tone arm is shown dropping onto the record at the start of the music. When the song finishes, the arm is still at the beginning of the record and then lifts off, as if the reject button was pushed before the record played.
Plot hole: When Carl is helping Molly out after Sam dies, he manages to find Sam's address book in a box, which he needs to launder the money at the bank. So why does he need to convince Molly to take a walk outside so Willie can break in the apartment and steal it? Carl knows which box the address book is in, and could have easily stolen it earlier when Molly was not in the apartment.
Suggested correction: Carl couldn't have stolen the address book earlier; it's possible he didn't know where it was, and he had to use the visit as an excuse, or it's possible he knew where it was but was thwarted because Molly wouldn't ever give him a chance to steal it, since she wasn't leaving the apartment. And he couldn't steal it later, because Molly wasn't leaving the apartment. His only chance was to lure Molly away so that Willy could come in and get it.
Since he worked at the bank with Sam, he could, without raising any red flags, simply ask to copy a few numbers from the book. Also, while he was walking with Molly, how did he contact Willie and tell him to go in? They didn't have texting back then. And how did he not know Molly had come back, if she had been walking with him? Other than the obvious, fourth-wall-breaking excuse that he didn't want us to know he was the villain yet.
Factual error: Banker Carl (Goldwyn) threatens to kill Molly at 11 pm if he doesn't get his $4 million. Goldwyn goes searching for his money at Whoopi Goldberg's house. Goldberg is arguing with her sisters over whether to watch The Arsenio Hall Show or change the channel to watch Love Connection. In New York, where the movie takes place, The Arsenio Hall Show was on at 11:30 pm (already past the time he threatened to kill Molly) and Love Connection was on at 9:00 am and both shows were broadcast on the same channel.
Continuity mistake: Right at the end, when Molly can see Sam as a ghost before he goes to heaven, they kiss. After the kiss, Molly and Sam open their eyes at the same time but in the next shot, Molly just started opening her eyes.
Other mistake: In the restaurant scene, when Oda Mae and Sam are trying to convince Molly of Sam's existence, Oda Mae is prompted by Sam to reply "Ditto"as Molly turns to reply, Oda Mae is about to say something else and Sam motions with his hand for her not to say anything...Oda Mae isn't supposed to be able to see Sam, so why did she stop?
Visible crew/equipment: When Carl comes and takes off his shirt, he spills coffee on himself and gets half naked. As he rubs Molly's right shoulder, the scene switches to Sam in the chair. As he leans forward if you look just to the right on the marble wall, you can see a reflection of a man with a camera, blue jeans and blue shirt. No-one else was there besides those three characters.
Continuity mistake: When Oda Mae is with Lyle Ferguson, he asks her to sign a paper that closes an account. Then he gives her a another paper to sign that is yellow. When she hands it back to Lyle, it is white.
Revealing mistake: When Oda Mae and Molly are running from Carl, they go to the loft upstairs. As they are running on the planks, the camera shot is from the bottom, and you can see the faces aren't of Demi and Whoopi.
Revealing mistake: When Willy enters the apartment and heads for the stairs, Sam dives at him in anger and flies through him. In this shot you can see how poorly Willy was added into the scene. The coloration isn't even close and Willy looks 2-dimensional. (00:32:30)
Visible crew/equipment: Whilst Carl is sat at his computer trying desperately to access the account, a crew member is visible in the screen's reflection along with his.
Visible crew/equipment: When Sam follows Willie to his place, a crew member is reflected on the entrance door. A frame before there was no one around.
Continuity mistake: When Willie breaks in and he is attacked by the cat, the position of the keys left by Molly changes between shots.
Continuity mistake: After they give the nuns the money, when Oda Mae spits at Sam, a woman with short dark hair in a green blouse, green blazer and long green skirt is walking towards Sam, past Oda Mae. Sam then says "I love you Oda Mae," and the same woman is now walking past Sam towards her.
Continuity mistake: Throughout the whole movie, Mollys bangs are short. In the end when shes talking to Sam they are longer, below her eyebrows.
Other mistake: In the ending credits, it lists "cemetary ghost". It should be spelled "cemetery".
Continuity mistake: When Oda Mae goes over to Lyle's desk and sits down, we can see his nameplate on his desk which reads Lyle Ferguson. In the ending credits it's spelled Fergeson.
Continuity mistake: In the film, Willy shoots the lock off Goldberg's door with a Walther PP but when he is looking around the flat he has a Walther PPK.
Visible crew/equipment: After Carl rips the page with the passwords, he is typing on the office computer. The reflection shows some kinds of structure with shades which disappears in the wide angles, very likely the movie's lighting equipment.
Visible crew/equipment: After Oda Mae rings on Molly's intercom she turns around and a lighting shade is reflected on her sunglasses.
Other mistake: At the time Sam is shot his soul separates from his body, indicating that he dies, but in the next shot the ambulance is carrying him to the hospital in order to help him.
Suggested correction: If paramedics think there might be a chance to save someone they will continue treatment until a doctor has made the call to stop. Just because the paramedics continued to try to save him doesn't mean he hadn't already died, just that they were not yet willing to give up.
I've seen Emergency Medical Technicians and County Coroners call "dead at the scene" many times, without any attempt to resuscitate. In Sam's case, in this movie, he certainly seems to be dead, just a moment after the gun discharges.