Drive the cars through the wash first and get them squicky clean by washing , shampooing, drying and giving them luster with your specialized equipment. After you finish the washing part and they are pristine you can take them to the tuning area and customize them to the ghouls heart. Add sculls , rotten eggs , lightning stickers and pumpkins to make Halloween a all year round celebration. There is nothing like driving a tricked out car that resembles yourself and the ghouls pay good money for this achievement.