During the epilog, Stone & Keller are seen driving in the older brown Ford Galaxie with the standard seat upholstery. When they arrive at Keller's apartment they are now in the newer brown Ford Galaxie with the fancier cloth upholstery.
When Keller is talking to Stone about the case, he calls him 'Fred'. There is no Fred in the room.
Mike and Sydney walk from sidewalk to berm to street, three different surfaces, but the sound of their footsteps doesn't change.