I need to create an event for birthdays, I multiply the price by the ability, for example:
ask how many kids go to birthday if the price range 15 x 9 = € 135
if they are 8 children x 9 = 72 €. The price can also change according to the extras, if you want piñata would be. 15 x 9 = 135 + € 20 = 135 piñata +20 = 155 €.
What is important in principle as the price multiplied by the number of children going to the birthday.