There are three lists, and you need to complete them all to get the achievement. Get the car back to your garage, and use the nearby Pay'n'Spray to maximise cash by fixing it before taking it to the crane. When you find a car that is required for the current list, there will be a notification in the top left of the screen. The better condition they are in, the more money you will get for the cars. There will be a board near to the crane, listing vehicles that they want you to steal. Completing the Customs Fast Track mission opens up the Import/Export at the docks.
