Always assume you get extras or a bonus if it there is an opening to do so. If you buy a dozen cookies for example you may imply that you assumed it would be a baker’s dozen rather than twelve cookies. If you are purchasing a new gun ask about the cleaning kit that comes with it. If you are buying in bulk always ask what the discount is for doing so. Look for ways to imply this assumption rather than simply stating that you assume something to be true. If they have to correct you that leaves you an opening to request a lower price.