After the fight in the hardware store with Jonah, Dexter runs over his brother with the rental car. This is the only time that the rear of the rental car is missing the Ford emblem. The other shots showing the rear of the car have an emblem.
Dexter's gloves disappear after he ends his phone call with Debra while on the boat. He is wearing black latex gloves while he is on the phone. He ends the call, turns around and when advancing the throttle at the helm of the boat, he is no longer wearing gloves.
The motel clerk gives 'Dexter' a dollar change. In the very next shot he gives him the change from a different location at a different angle.
Entering the elevator with Laguerta, Deb carries a satchel full of papers and staggers slightly with the load. Leaving the elevator, she carries it without effort.
Dexter throws the body of the motel clerk into the corn silo and it is shown sinking into the corn as if the corn is a liquid or semi-liquid when in reality the body would have remained on top or at most slid to the side if the the corn was higher in the center.
Rudy's "ghost" calls the murder weapon a razor blade. Technically, it is a straight razor.
When you see Dexter driving to confront the motel clerk after being at Jonah's house, there is a Florida license plate on the front of the car. Florida only requires license plates to be in the back.
When Dexter pulls in front of Jonah's house and opens the trunk for his knives, the camera pans palm trees above the house. The setting is Nebraska and there are no Palm trees there.
The motel clerk pulls a gun on Dexter and cocks it, Dexter somehow reaches a couple of feet behind him, takes a pitch fork off the wall,lunges toward the clerk, stabs and kills him. All the clerk had to do is pull the trigger of his gun.