There are no fees charged to sellers* other than standard PayPal charges, where PayPal is used.
Please note the following where PayPal is used:
In addition you will receive an overpayment from the buyer for the Twickets fee they have incurred for the transaction.
PayPal will then debit you this overpayment in a separate transaction, and transfer the amount directly to Twickets.
This is NOT a charge to the seller, merely a transfer of the initial buyer's fee to Twickets.
*excepting certain partner events