Hi Adrie,
Good question! Yes, Event Calendar PRO’s additional field feature is one way to go about it, but does take a bit more custom development to accomplish than you may consider ideal. For example, you would need to move the fields below the existing cost field because additional fields are located elsewhere on the single event template by default.
Another way to go about it would be to use Advanced Custom Fields. That would allow you to create custom fields in the event post editor and you could add those to the event view templates where you would like them to display.
It’s also worth noting that our Event Tickets Plus add-on does change the event cost field to display a price range for events that have multiple tickets associated with it.
Does this help answer your question? Please let me know.
Cheers!
Geoff