After Fred brings the dog poop in and gets it all over the carpet and the chair he tosses the ink and Elizabeth has to lunge to catch it. The dog poop isn't on the carpet when she lands.
Young Lizzie's eyes are a bluish/green mixture, while Lizzie's as an adult are dark brown.
When Lizzie and Charles are arguing at the car dealership, a woman stands in front of a red car. She asks to test drive it but in the next scene the car is gray and is a convertible.
when drop dead fred is smashing the engine the red cover to the switch under the danger light near elizabeth is down but in the next scene it is up.
When Lizzie is in the restaurant with Mickey, Fred pours her glass of water into her lap. When Fred puts the glass back down on the table, you can hear that the glass is made out of plastic. A few seconds later, Fred is holding Lizzie's wrist and knocks the glass over onto the floor, which then shatters as if it was made of glass, not plastic.
Obvious double when Fred slides down the banister.
As Fred tries to pull his head out of the fridge, you can see his real hair under his arm.
When drop dead fred gets his head slammed in the refrigerator the side of it compresses showing it is not real but a prop.
When Fred slides down the handrail before he can even get to the end of the hand rail a sound is made as if he hit his private part on the cap. The next scene is showing him At the end of the handrails in pain.
When Fred is in the engine room of the houseboat, you can see the paddle wheel in the background moving back and forth while the boat is still moving forward
Fred pulls the downstairs phone cord out of the wall, and this is shown to cut the communication between the parents using the upstairs phone and the police. In fact, old landline phones in a house are wired in parallel: Disconnecting one phone doesn't break the others' circuits.
When Elizabeth and Fred are on the boat she asks Fred, "What is that water doing there?" He replies, "I don't know," but his mouth is saying something else.
When Fred slides down the banister, he shouts, yet his mouth is closed.
The jack-in-the-box starts playing quickly in the middle of the night. When Elizabeth turns on the light it stops, but when it starts playing again, it's at a different part in the music.
Just after Elizabeth's mother seals the box which Drop Dead Fred is in, a yellow tape-marker on the floor can be seen to the left of the marble-topped table and a blue one can be seen to the right.
When Liszt is in the phone booth in the beginning, you can clearly see either the cameraman or director (wearing sunglasses) in the phone booth glass reflection.
After makeover scene, Elizabeth & mother walk into the house. Mother picks up the letter, which she can clearly see/handle. This letter turns out to be from (imaginary friend). How did imaginary friend write a visible letter? Never clarified that Elizabeth did this herself to give herself an excuse to leave, or if she's insane, as it seems she truly expects to see her husband as the letter promises.
In the scene where the nurse gives Elizabeth the pill to make Fred go away, the boom mic is visible for a second above her bed.
The boom is reflected in the picture on the wall, after the nurse throws Elizabeth back into her room and calls her a flake.
When Charles is taking the woman for a test drive in the car, Elizabeth pulls up next to them, and the boom is reflected in her door before it moves out of shot, though the boom pole is visible throughout the scene.