Far into the story the film shows the view from Mr. Neville's office window, allowing us to see a few applicants. Among those is a couple whose application had been rejected early in the story by Mr. Neville. Obviously the same set served different scenes that were far apart in time.
During the opening scenes of the movie the lizard that they have been hunting is killed and when they are carrying it back to their home the lizard is first carried one way then switches with the change in camera angle and then changes back.
The girl's shoes and clothes were far too clean and intact for a thousand mile walk. The girl's hair wasn't dirty enough and didn't grow during the journey back to their home. The girls looked like they went on a 10 mile hike with very few food sources, lack of water, lack of hygiene, and lack of injuries to accurately depict authenticity.