Head to the marked area and track down Pagani’s car. There are no indicators in the map so you have to listen to the beeping noise from the tracker. The closer you get, the shorter the intervals and the faster the beeping will become. Also, as you begin to home in the signal’s source, the search area will begin to get smaller and smaller. Obviously, you’ll immediately know the location you should be going once you see a large congregation of red blips in your minimap.
Make your way to the garage’s entrance and take out the two guards. Silently break in the door and creep your way to the offices where the printing press for counterfeiting money is located. Take out the isolated guards silently then get the Vargas painting from the wall in the main office. Open the next door; even if you didn’t make any noise, once you open the door, Pagani and his men will automatically detect you and he’ll escape using his car. Take out his guards then jump into another sportscar in the garage or quickly go outside and use your vehicle.
Chase after Pagani and disable his car by shooting his tires. Once disabled, leave the vehicle and take out his bodyguard. He’ll also make a run for it, probably to ride another vehicle. Don’t allow him to do this and attack him to disable him. Once he’s down, interact with him to complete the takedown mission and trigger a cutscene.