It doesn't really matter what the contest it at this point. Let's say it's coin tossing for the sake of argument. Or, my widget can fly higher than your widget.
What would be an acceptable "Fee" to charge for hosting a contest, or what should I consider taking into account for determining said "fee". I would guess, complexity of contest, entertainment, etc...
My initial thoughts are at least 10%, so in the above example, the winner of the contest would recieve 190L$ and I would recieve 10$L for hosting the contest. Players would be able to bet as much as they want, of course

In a 1st, 2nd, 3rd place situation (example)
Players bet 100$L each...with say 10 contestants, making the pot 1000L$.
1st 50% (wins 500L$)
2nd 25% (wins 250L$)
3rd 15% (wins 150L$)
Hosting Fee 10% (100L$) (notice the fee is applied to the pot at the same time as the prizes to maximize the winnings for the contestants.)
Consolation prizes for all other contestants.
Thoughts?