When Barney leaves the bad guy's office at the end of the mission, he summons the elevator by pressing the up button. But the office is on the top floor and Barney would be going down.
If the elevator goes to the roof, that would explain why there would even be an 'up' button on the top floor. Or it's simply a design flaw in the building's planning. Regardless, it is the lone elevator where Barney is in the building and either button will call the elevator to his floor. Once inside, he can choose whatever floor he likes. But it doesn't matter what button he pushes.
If the elevator goes to the roof, that would explain why there would even be an 'up' button on the top floor. Or it's simply a design flaw in the building's planning. Regardless, it is the lone elevator where Barney is in the building and either button will call the elevator to his floor. Once inside, he can choose whatever floor he likes. But it doesn't matter what button he pushes.
When Jim and Willy are getting ready to take Goslin in, the exterior of the car shows the license plate on the vehicle is an obvious fake, it has black lettering on a white background with no identification of what state it's from, making it appear to be just cardboard add-on.
When Hamp pushes Millie into Barney and Corely, you can briefly see a blue sleeve with red stripes on the right side of the frame.