I recently had this discussion with my Master.
Two schools I recently looked into charged between $80-$120/month, plus additional to be on the sparring team, &tc.
With my Master, I paid no more than $60/month, and during our discussion, he said that $35/month is a more approporiate rate. Master Guthery adhered to the principal of making Taekwon Do affordable--the art is more important than money, for the real profit if the art is helping others achieve self cultivation. So, if a student could not afford to pay the tuition, he made arrangements to have them come in and clean the dojang, &tc. as compensation. In all of the schools I have looked at, none other has offered a similiar option.
Now, in the most traditional sense, students most commonly didn't pay monetary compensation in all cases. Often, students would live in the dojang and clean, chop wood, &tc. to earn their keep.
That said, Taekwon Do is a lifelong attempt to acheive perfection. So, if one can put a price on such an investment, it would never return appropriately to the investment and would never be a return one could collect, as the moment one achieves perfection in the art is after one has ceased to subside in this world.
