Hi Dujon,
Thanks for the interest in our plugins.
I can answer your questions.
To let visitors submit events we have the Community Events Add On that works without buying Pro.
https://theeventscalendar.com/product/wordpress-community-events/
We have no feature to take appointments, just to create events.
And as for your other three points:
– Require payment to submit events (Paypal or Authorize.net)
– Take offline payments and register them for online usage
– Apply member-discounts while charging full price to general visitors
We do not have any features to do those three above.
Those three could be possible with Community Events, but would take customization on your part, which is beyond the support we can provide.
Let me know if you have any follow up questions.
Thanks