When Tom first reads Marguerite's letter to God, it's says she lives in apartment 2-F at the Normandie Arms. But then when Tom addresses the envelope to Marguerite, he addresses it to apartment 22-F. When Tom arrives at the Normandie Arms to get his money back, Marguerite is speaking to the other renters, she says she lives in 2-A.
Tom's can of drink changes from a Pepsi to a Diet Pepsi.
When Tom goes into the water to stop James from committing suicide, he removes his shoes and socks, and after getting out of the water, while talking to James, he suddenly has shoes on.
Tom is shown driving a mid-1980s model Chevy S-10 pickup. In one scene, a shot of him turning his ignition key shows the steering column and interior of a completely different vehicle.
The envelope that Tom puts the $5,000 dollars in moves around. He first puts it into his pocket, then you see it in his breast pocket, then it disappears.