Hi Chris,
Thanks for checking out our plugins!
We do indeed have a pro version of Event Tickets. Event Tickets Plus will let you add custom fields to collect additional information from attendees (for RSVPs and paid tickets) when they register for an event.
Limiting the number of RSVPs by user is not something that is currently available out of the box, but it can be done with a customization. We are limited in the amount of support we can provide for customizations, but there are some snippets out there that you could use as a starting point (like this one or one of these) if you’d like to make this change.
Another option would be to use a WooCommerce ticket instead of an RSVP and set the price to “0”, which would allow you to take advantage of some WooCommerce features and extensions. For example, this third-party plugin called WooCommerce Max Quantity or the Min/Max Quantities premium extension from WooCommerce might help you out here.
We do offer full refunds within 30 days of purchase if you’re not satisfied with the products, so please feel free to give ET+ a test run! If you have any other questions, please let me know.
Thanks,
Jennifer