[Sangetsu]

The going rate for one-on-one private lessons is 3000 yen per hour. Anything less than that is not worth the trouble, considering the hour itself, and the time spent getting to and from the meeting place.

Most conversation schools will charge about 3000 yen per hour to students, but they charge as much as 5000 yen per hour for private lessons.

Even if your your English is not first rate (you should see Japanese "English" teachers who work in the schools), you should accept no less than 2000 yen per hour. Let your student try to find someone who accepts less than that, there won't be anyone who does.