Pick out the best house to renovate, AKA flip ... what to look for when buying a flipped house

Many of us want to renovate or flip houses. But what do we look for when we're trying to buy or acquire the right property to flip? Also real estate agent out there what are you looking for when working with a renovator? And buyers out there what are you looking for and hope to find when buying a house that has been flipped? What do you watch out for? And flippers out there what do we inspectors look for and how can we keep you out of trouble?