You may want to specify a minimum or maximum number of tickets per order, for example, if you offer a group discount for purchases of over 10 or more tickets, or if you're taking registrations for a sports team of a certain size.
How to set up a minimum or a maximum number of tickets allowed per order:
Navigate to the edit event form or create a new event, and from there:
Create all of the ticket types you want to sell and set the quantity to the maximum available.
Click on 'Add a new ticket group'.
Give your group a name that represents your tickets.
Under 'Add tickets', tick the box for each ticket that should be restricted by the order limit.
Click 'Save ticket group'.
Your checkout will look something like this: