I am having an 80 guest wedding. The ceremony and dinner are upstairs. The reception (dancing) and cocktail hour is downstairs. So Basically will have the ceremony upstairs, downstairs for cocktail hour, back upstairs for dinner, and then downstairs again for dancing. Obviously we need about 80 chairs for ceremony and dinner alone, but how many extra should we order for the cocktail hour and reception? I don't want chairs being toted up and down stairs for switches.