As the characters clean up following the dinner, the turkey platter is simultaneously on the kitchen table and the dining room table.
At the beginning, during the graveside service, the sun is on the verge of setting, yet moments later the funeral luncheon at the Cooper home is bathed in mid-day sun.
The fog completely disappears after Harold's brief close-up shot when he and Nick are jogging through town.
Alex was living with Harold and Sarah and it's later revealed that Alex committed suicide in their basement, however, the movie opens with them receiving a phone call that Alex has died. The police, medics and coroner would have all been to their house and the police would have interviewed them.
However, Harold and Sarah own more than one home and are seen at their other home at the beginning of the film when they receive the call that Alex was found dead. Harold mentions this at the funeral, stating that he and Sarah were at their other house with the kids when the suicide occurred. They were letting Alex and Chloe live in the basement apartment of their summer home, the home where the majority of the film takes place.
However, Harold and Sarah own more than one home and are seen at their other home at the beginning of the film when they receive the call that Alex was found dead. Harold mentions this at the funeral, stating that he and Sarah were at their other house with the kids when the suicide occurred. They were letting Alex and Chloe live in the basement apartment of their summer home, the home where the majority of the film takes place.
As the movie opens an older couple is walking up to the church, but both were clearly standing still arm in arm until they got their [late] cue to walk.
When the cast is eating their first dinner, a crew member is visible through the window on the right.
When Nick and Harold are walking, Nick's (William Hurt's) wireless microphone can be seen clipped inside his sweatshirt.
In one scene, Michael is eating Dreyer's ice cream from the carton. Dreyer's is a brand that originated in Oakland, CA, but when their distribution went nationwide in the early 80s, they ran into trademark infringement trouble with Breyer's Ice Cream, because of the similarity in both the names and the script logotype used by both companies. An agreement was reached that Dreyer's would go to market East of the Mississippi River as "Edy's Ice Cream". So they could never have purchased Dreyer's Ice Cream in South Carolina. But they could in Hollywood, which is no doubt where that scene was filmed.
Harold violates the law by telling Nick that a big company is going to buy his company so Nick should trade on that info so he can clean up his life. Harold also gave that info to Alex and Alex was able to leverage that info to make the money that he used to buy the house. Alex couldn't have profited from that info because it hadn't happened, yet.
Sarah's concern about putting everyone up in her huge house would actually make sense. Despite its size, the house has only four bedrooms, one in each quadrant upstairs. Putting Nick in the attic, and Chloe in the basement, Sarah and Harold in the master, and Richard and Karen in another, would leave only two bedrooms and three more people to accommodate. Yet everybody seems to have their own comfortable room throughout the film.