Hi Jennifer. Thanks for your question.
All our add-ons are independent (i.e. don’t require any other paid add-on)… except for Community Tickets, which states so on that product page.
So for PRO or Community Events, you can buy one or both. If you buy both, the Community Events front-end form allows users to enter “custom field” information that you add via the PRO add-on.
Last but not least, we have a pretty great Refund Policy so you can buy one or many of our add-ons and thoroughly test them.
Let me know if you have any follow-up questions.