Hello,
Thanks for purchasing WooCommerce Tickets. I can point you in the right direction here.
All our plugin does is create tickets as a product with the attendees list and the tickets on the event.
WooCommerce handles the rest. I found this documentation from WooCommerce that looks to enable Surcharges in WooCommerce:
http://docs.woothemes.com/document/add-a-surcharge-to-cart-and-checkout-uses-fees-api/
That might get you close to what you are looking for.
All tickets are WooCommerce Products and appear there so you maybe able to modify the Ticket Product Directly. A product is created for each ticket you create in an event.
Let me know if that helps.
Thanks
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