Depends on your major or hobby. If the major is not optical sketch for the exam, the tuition fee is about 1500-3000 a month, and the more the exam comes, the more expensive the studio is.

If it is an ordinary study hobby, 600- 1000 a month is enough to ensure a lot of study time.

Sketch is boring compared with others, but it is easy to learn to draw a unique sense of accomplishment after you like it. You go to the studio where you want to take the exam.

Hobbies can teach themselves, buy books and copy by themselves.