At around 53:48, when Ove is on the platform the clock shows 6:45am. When he comes back home to rescue the cat and goes upstairs, the little alarm clock shows 6:20am.
It is very obvious that two cats were used to play the one in this film. One is very white and the other has a great deal of tan in its coat.
Ove's blue suit right shoulder seam is torn when he rescues the young man from the track. When Ove hangs up the suit to air out at night, the seam is repaired.
When Parvenah runs to check on Ove for not shoveling his walk, it is snowing heavily. When she gets to his bedroom, the view through his partially opened blinds shows it is mostly sunny and not snowing.
Throughout the movie, there are several popular models of Saab and Volvo. However the registration plates on some cars are too modern. One example is the light blue Volvo 142/144 that has a plate issued more than 20 years after the car was made.
To emphasize a Spanish holiday atmosphere, music by Demis Roussos is played. Demis Roussos is a Greek singer, and his music would be more suitable for a Greek holiday atmosphere.
In a flashback sequence around 44 minutes in, young Ove talks to Sonja about cars and mentions Saab 93 but he calls it "Nio tre" ("Nine three"). While the Saab 9-3 introduced in the late 1990s was called "Nine three", the 1950s model he's talking about was called "Ninety three".