We're a dental clinic in Kadıköy with four specialist doctors. A few months ago we shook hands with a software agency to build a patient tracking and appointment management system. During the proposal stage, we discussed that SMS notifications for appointment booking 24-hour confirmations and 2-hour reminders would be included in the software. The agency quoted 65.000 TL for development and initial setup, which we approved and kicked off.
The system has been live for two months. We handle an average of 1,200 appointments a month; between confirmations cancellations and reminders, we send over 3,000 text messages monthly. Yesterday, the agency billed us an extra 1.800 TL for SMS sender ID setup and credit consumption. We assumed this operational expense was covered by maintenance and system costs, but the agency claims it's a variable carrier expense.
In appointment projects like this, who is typically supposed to bear SMS notification expenses? How should this cost have been defined as a distinct line item in the proposal and contract phase so neither the clinic nor the agency runs into friction?