If you are not sure about the exact amount you need to pay for your order, go to your inbox and search for the confirmation email of the order you completed at Papaki. The email subject is: "Order Information No. 'xxxxxxx' at Papaki ", where 'xxxxxxx' is the registered number of your order.
Then, you can complete your payment with money transfer/bank deposit, to one of the cooperating banks.
You can follow the renewal process through your Control Panel, to check the total cost. Bear in mind that you can renew multiple domain names at the same time. Log in to your Control Panel, here.