HiĀ Federica,
Thanks so much for your interest in our plugins! While Event Tickets Plus does not provide any built-in functionality for a minimum number of RSVPs at this time, you can achieve this effect by having all new ticket orders set to a status such as “Processing” until the minimum order threshold is reached. Once you’ve reached your target figure, you can then manually move your orders to “Completed” status and have tickets sent at that time. You can learn more about how to set this up on our Knowledgebase at the links below:
If you need to have this function performed automatically, you can likely achieve this effect via custom development, though unfortunately our support team isn’t able to assist with modifications of this type. We do, however, maintain a list of third-party developers who work with our plugins and would be more than happy to discuss the details of your project!
I hope that helps to get you started here! Thanks again for stopping by, and let us know if you should have any other questions!