When you're a high-flying star with a multimillion-dollar bank account at your disposal, not only can you snap up the house of your dreams, but you can spend a small fortune making it entirely your own. From Pharrell Williams' mega-mansion makeover and Selena Gomez's fabulous house flip to Brad Pitt's dusty garage transformation, these world-renowned celebrities show us how to turn a house into a show-stopping home. Click or scroll on to see the unbelievable before and afters...