Use the Rhino to complete the vigilante missions easier. Additionally, start the mission, put the vehicle in your garage, and exit so that the door closes. Enable the "Destroy all cars" code. The criminals will be killed. Run back to the garage, hop in the car, and repeat. This is also a good way to quickly gain more money and status points. Get an FBI Rancher and drive onto the Julius Thruway in Las Venturas. Start Vigilante mode and begin driving around the highway. Just stay on the highway, and you will notice that the criminals start dying for no apparent reason. Just drive for about twenty minutes to get the 150 armor award easily.