Continuity mistake: When Happy is trying out for the hockey team, he sends a slapshot in front of the coaches and it breaks the glass. In the next shot the glass is intact. (00:04:07)
Revealing mistake: When Happy tosses the IRS agent out of Grandma Gilmore's window, he falls down the steps outside and it is blatantly obvious that he is wearing kneepads under his suit pants. (00:09:06)
Continuity mistake: When Happy and his Grandmother arrive at the nursing home, Happy puts his Grandmother's suitcase under the bed. In the next shot it's not there anymore. (00:09:45)
Continuity mistake: At the beginning when he enters the apartment he barges through the door leaving it open but when the lady walks in she has to open the door.
Revealing mistake: When Happy jumps on the alligator in the pond, it is very noticeably a rubber (fake) alligator.
Other mistake: When Shooter is telling Happy to meet him and the other pros at the 9th green, everyone in the background is talking among themselves, then suddenly are closer and staring at them. (00:31:47)
