When Jonathan drives drugged down the mountain and spins to a stop, he is clearly on the very edge of a cliff about to go off and there are no trees around him. When the closeup camera comes back to Jonathan waking up, still in the car, trees are all around and he is no where near the edge.
Jonathan is driving on the freeway while talking to Jennifer on the phone. In the next shot he's driving on a city street, but was never seen to exit the freeway, and is at the same place in his conversation with Jennifer.
When drew forces Jennifer into a staircase, she has two barrettes in her hair. The next time she's seen, the barrettes are gone.
No doctor would give a non-medical person the keys to a home stash of medicines.
When Drew is looking for a drug in his wife's book, he focuses in on a yellow capsule that lists both the brand name, Macrobid, and the generic name, nitrofurantoin. That's an antibiotic used for urinary tract infections, and would not cause the doping effect that he intended for his victim. It also wouldn't dissolve in a drink instantaneously.
It's clearly a stunt double for Stefanie when she's on the roof with Drew.
When Jonathan is outside, looking at the apartment building with the binoculars, he spots the apartment of the murdered woman. It's about 1/2 way up the building, in the middle of the floor. When he and Jennifer arrive at the door, he says, "top floor, corner apartment."
When Jonathan is outside, looking at the apartment building with the binoculars, he spots the apartment of the murdered woman. The closeup scene shows a bright yellow patio furniture on balcony, but the next scene is full camera view of building and no yellow furniture to be seen.
Jonathan took a cab to the dinner party after his accident, but the car is at home when he and Jennifer arrive there. The next day it's still downtown where he abandoned it.
When Max looks at the ticket on Jonathan's car he doesn't check the time on it. That would have been a clue as to what had happened the previous day.
Jennifer said, "acting so strange" rather than the "acting so strangely". As a journalist, she'd know the grammatically correct phrase.