There are no joining fees or subscriptions.
For American Express cards, a 1.95% + GST convenience fee is included in the payment. You will more than recover the convenience fee with reward points, tax savings, early payment discounts, and administrative savings.
The blended rate convenience fee for MasterCard and Visa credit and debit cards is 1.4% + 50c + GST.
For more information, see Reward Payments.