James and Darnell fall off the yacht into the water. They then immediately climb on board again, and are only slightly damp.
Before Martin's yacht disembarks, all fenders are brought aboard. After Mayo & Chocolat leap onto the yacht, another shot shows two fenders are again next to the boat in the water.
James is charged with violation of federal laws. If convicted, he would be sentenced to federal prison. San Quentin is a California state prison.
The original IBM PC used by Martin had a dual disk drive instead of a hard disk. As such it would be useless without the floppy disks that any data would have been stored on. They should have stolen the floppy disks and not the computer.
When Darnell is driving James to the hospital with the shank/knife in his head, Kevin Hart's character refers to him as Will, when he asks him to do a memory game and name 12 months.
When James picks his car at Darnell's cleaning service for the first time he drives away with the trunk opened. You can not see the trunk, but you can see that on his Audi A8 driver's panel that the trunk is open through a red sign right on the center of the panel.
When James is talking to the guys in the park that he is supposed to start a fight, the shadow of the boom mic moving is visible on the trees behind him.