During the 1977 Era go out of your safe house and turn right. Keep going straight until you run into an alley way that will lead you to a place where you can customize your car with new bumpers, wheels, side skirts, body kit, ect. To customize for less money, complete the game and choose the car or bike store at Rays. Now go back to the 1977 Era to customize for ten times less money. Note: The customization area is not available in the 2006 Era.