Add-On Inventory
Unlike Giveaways, there isn't a section that is separate for add-on inventory. If you would like to add an inventory amount you can do so by click the plus sign next to Advanced Options when setting up your Registration Add-on.
When you enter the Total Quantity Available it will notify registrants when they purchase an add-on and there are not enough left. It will not let them continue to the purchasing page until they change it to the right amount. It will look like the image shown below as well as a Submission Error message in red at the top.
