At least two people are required for this, with one of them being able to get the mission from Lester called "Cops Capacity". In this mission you will get a Vapid Dominator with bulletproof tires. Complete the objective until you must drive to his compound to end the mission. Allow the other player to get there alone, while you remain seated in the Dominator. When the mission ends and the game resumes, you will still be in the Dominator. Drive it to a garage and place a tracker and insurance on the car and it is yours, with a free bulletproof tires upgrade.