he wants 10% on sponsers and 20% of the purse? WTF!!!
You are PAYING HIM for the mat time, instruction, ect. Your classes are not free. He's just trying to squeeze every bit out of you that he can get.
I'm not saying instructors shouldn't be paid. Mats, equipment, rent, and time cost money. But asking for a percentage of your purse sounds a little shady.
What if your college asked you for 20% of your pay check? You payed tuition and owe them nothing.
You are the guy in their fighting and risking your health. The money is yours. Do not pay him.