In a spray coating apparatus having a spray coating gun with a gun body and a coating material tube, a nozzle provided at the front end of the coating material tube, the coating material tube extends from the nozzle at the front end of the coating material tube to a connection piece at the rear end of the coating material tube. A reflector is a generalized packet router program. The GPS-based navigation system continuously determines the motor vehicle exact physical location in a region that is intermittently or continuously uploaded to a remote computer via the wireless communication network.