To register articles we will go to:

Finance → Stock Control → Products

We will open the next window with all the items that we have already registered. We will click on the "New" button to create new articles.

We will see the following window with all the data that we have to fill in. 

For example which family or brand have to be fill it.

If we want our customers to have the ability to add an item during the court booking process through the app, we need to click on the 'Use in Online Bookings' button in the item profile.

Within this tab, we can enable the purchase of the item for each sport, specify whether the item can only be charged for a single unit, or if it can be acquired in multiple units, set the maximum quantity of units that can be added to different bookings within the same time slot.