Other mistake: Sarah steals the tranquillizer syringe (which is no small syringe, either) and supposedly slips it in her sleeve. Problem is, Nicole Kidman is wearing a pretty tight dress with sleeves that go up to the elbows. There is no way for her to hide the syringe that way (and in fact the actions of hiding the object and then later in the movie pulling it out happen in shadowy close-ups). (00:36:20)
Other mistake: Kyle and his daughter manage to free themselves burning (at least in part) their scotch tape bindings. The robbers don't realise that. Try to burn similar tape with a lighter; the smell (that they can't mask) is gonna alert anyone, especially when they get this close. Later Kyle is working the weakened tape and in close-up we see just his forearms, but the kind of movement he does is impossible to make without moving the rest of the arm, and the bad guy (with his accomplices) is literally looking at him at that moment. (00:50:00 - 00:54:00)
Other mistake: The gasoline at the climax of the movie catches fire, which is absolutely fine...but the fire spreads with the same intensity and speed across the money pile which was not touched by the gas. And it does it with a pattern, too. But the gas never got there. (01:21:45)
Other mistake: Succinylcholine paralyses you for about 10 minutes; in the movie it lasts way longer, and the bad guys were planning to use it instead of ropes and cuffs. It would have bought them a really short time, surely insufficient to make their planned escape to Mexico, while tying them up with just about anything (zip ties, scotch tape) would have given them potentially hours.