This help doc and video will demo how to set the maximum quantity of tickets a patron can order on both general admission and assigned seating events.
Remember to set this up in your pricing template before loading it into your event.
NOTE: The max qty on general admission tickets is the drop-down display amount. This setting does not limit the number of tickets a user can buy per transaction. It is just the qty display. For example, rather than the default 10 tickets for general admission tickets - you may want to show 50 tickets in the drop-down menu.
To limit the qty a user can buy per transaction go to MANAGE EVENT DATES and adjust the limit qty per section box. This will limit the number of tickets someone can purchase per transaction.
VIDEO DEMO