First of all, the income of a private school depends on the amount of student contributions. Accordingly, the more there are, the higher the income level. But at the same time, the costs of maintaining a large room, a larger number of teachers, also increase. Also, the amount of income is influenced by the variety of services provided. Taking a language center as an example, the more languages taught, the higher the likelihood of attracting students.
In terms of numbers, you can preliminarily calculate: the annual tuition fee for 2-3 grade school for 10 months is 2-3 thousand dollars. At the same time, the cost of education in kindergartens, out-of-school institutions, in equivalent to public schools and vocational schools will be slightly lower. As for narrow-profile courses or training in special professions, everything here depends on the demand and quality of teaching, on the innovations that your school will offer. After all, in any business it is always important to find your niche!