I wrote a small personal software for a teaching center to manage schedules: Its functions include categories for lecturers, students, time slots, class categories (with options to choose colors, select days of the week, and time slots when adding or editing classes), and the ability to sort which lecturer teaches which class and which student attends which class. It then displays a consolidated view as a master schedule based on class schedules and schedules of students and lecturers (the schedule can be viewed by lecturer, student, or class block), and a dashboard for statistics on the number of students, classes, and lecturers. I completed this within 2 weeks from data design to coding.

What fee should I charge the center based on these functionalities?