It would be nice if the system was smart enough to apply a 90-minute voucher to a 60-minute appointment and then have a 30-minute remainder. On the same topic, it would be very convenient if the system was smart enough to know that if a client has a voucher in their account that could be used to partially pay for a service that you would be given the option to do so. It something isn't exactly the same price then potential payment options are ignored.