So, my venue suggested that once I get the final count, to add 10 to it so that I would have an extra table just in case, people would have more freedom to move tables.I'm hesitant to do this first because obviously it will add more cost but second because people have told me that people who rsvp'd yes will not show up.So I am just wondering how everyone else's experience has been when estimating the final headcount?  Should I add an extra table?  Or will no shows and unexpected additions really just even out in the end?