When Marcus is on the hospital roof in nothing but a gown, the sign on the adjacent building says that it's a Grand Hyatt hotel. Miami doesn't have a Grand Hyatt, but the one shown is in Atlanta, a sign that most of the movie was filmed there.
The movie's finale is set in Islamorada in the Florida Keys, as shown on the nav screen of the helicopter that flew there. The aerial shots of the vast, hilly forests it supposedly contains are obvious fakes: most of Islamorada is less than 1,000 feet wide, and like the rest of Florida, it contains zero natural hills.
Will Smith calls out to Martin Lawrence as "Mike" when following him to the hospital elevator, even though Lawrence's character is actually "Marcus."