Whether you are organising a paid ticketed event, a private view or a talk, you can provide your visitors the option to purchase additional items when they proceed with their booking.
The 'Extras' feature can help you increase your revenues with the sale of certain items that visitors may be interested in purchasing but many times unaware of, or that perhaps they could not be bothered to ask for the price.
Adding extras is very easy, just click on Edit and you will see this option next to 'Tickets' (gif below). Be aware that the addition of extra will not affect your event availability.
You can see below an example of how the additional item purchase will look like on your booking.