The CERTO /iPAY is a self-service payment terminal that is suitable for different checkout scenarios. For example, it can be used in a configuration with mobile self-scanning modules or with attended or self-service checkouts. A transaction previously registered at a checkout or mobile self-scanning module is retrieved at the CERTO /iPAY by scanning a customer card or the receipt in question. Afterwards the customer pays by card and leaves without the need of an assisting cashier.