Will is walking in town and looks into the café as a man and a woman - the woman is wearing red boots - walk towards him. He goes in, talks to the police officers and leaves a few moments later. When he does, the same couple are walking towards him again in the same direction.
(at around 14 mins) When Will leans the ladder against the house the rungs are facing backward, the rope pulley on the right hand side. In the following shot, from his POV looking at the footprints, the ladder has been flipped to the proper position.
When Jack talks to the hit man on the phone to prepare for the murder, the hit man tells him "I see Jack's wife outside right now." Since he is talking to Jack at that moment, he should have said "I see YOUR wife outside right now," and not refer to him in the third person.
In the diner where Will is asking the police officers about the murders, the front shot of the officers is flipped as indicated by the text on the menu in the background as well as the seating of the officers switching between shots. That's because it's being seen through the mirror behind the counter at the diner.