they all come from different perspectives and probably amounts they charge as well. why not be cheap - and take from a student of a student. or a student of a teacher and pay less and get the same information. that's my motto. i mean - i took from an excellent teacher at west chester. i have no desire really to take from the top yet - because my playing doesn't merit it yet. i suppose one knows when one needs that quality - but my -they probably charge at least $100. per 1/2 hour or something.
personally, i felt my last teacher could have charged anything he wanted. being young - sometimes teachers don't know what they're worth - or are extra nice to get a load of students going. perhaps what the market will bear - too - in the long run. but, as i see it - some people are BORN teachers. they know how to play and teach and they don't waste time.