When Jessica goes into town to buy eggs, there are only roosters seen. No hens are seen at all.
When Jessica opens the door to the house, it has a doorbell at hip height, but once she and Duncan are in the house, the door now has a door knocker at head height.
Throughout the film (most notably at exactly 7:01 into the film), you can see the front license plate of the hearse is a New York plate, 1Z-7663. However, If you pause it just right (at exactly 41:27 into the film), you can clearly see the hearse's front license plate now reads 4G-3375. Later on in the film (at exactly 1:00:08), you can then see the front license plate has changed back to 1Z-7663.
The straps on Jessica's bathing suit, when Emily pushes her off the dock and "plays" with her in the water, are alternately on and off her shoulders.
Emily's hair is down as she applies lotion to Jessica, but suddenly tied back as she jumps into the water. After being in the water for a moment, her hair is down again.
When Duncan hands Jessica the "mole" in the cemetery scene, it can be clearly seen that it is a field mouse and not a mole.
Jessica is shown from the back at a gravestone just after the woman in white has appeared. Just before Duncan says, "Hey Jess, come on, we've got to get moving," the gravestone she is at moves - it is not a real gravestone.
While playing guitar, Emily is clearly not actually playing as she does not change chords or strum correctly.
When Emily is playing the lute in the kitchen, her strumming is different from the music and the sound is that of a guitar, not a lute.
When Jessica first goes inside the house, Duncan says "Well, let's go in"; she visibly replies "Okay", but it is not heard on the soundtrack.
The old man's voice when Duncan asks him where there is an antique shop nearby does not match his mouth.
(at about 1:00 into the film) When Emily sings in the kitchen, the knee of a crew member can clearly be seen in the left corner of the screen.