Continuity mistake: After the opening credits, while the red car's being lowered, the angle changes to a close-up and all the people in the background change positions: A man behind the red car walks around it twice, and 2 people appear from nowhere next to a white car.
Continuity mistake: Back in LA Charlie talks to Dr. Bruner about Raymond's future. Charlie's nonchalantly hanging hair in front is all combed back from the moment he says 'I never called him back'. (01:48:15)
Continuity mistake: As Tom Cruise walks to the Amtrak train with Dustin Hoffman near the end, they stop about 1 pace from the train door, but in the next shot the pair walk about seven paces to the same spot in front of the train door.
Continuity mistake: After the duo stops at a motel with pink neon, Ray starts reciting his riddle about the guy on first base again, which gets Charlie annoyed and he badgers him over it. After their little exchange, Ray is walking up to the side of the car as Charlie opens the door to their room. Ray is standing very close to the car, standing right on the yellow line of the parking space. The camera then suddenly jump cuts to a higher angle and Ray is now several feet back standing in the middle of the next parking space over.
Answer: Susanna was there as well; Charlie just used the "date" as a reason for the three of them to go down for a drink together. He knew Iris wouldn't show up.