What kind of commission can I ask for in boat sales?

I've been building them for years but recently I've been approached to help sell another guys fleet of varied new and used small craft. I willing to give it a try but what kind of commission would be fair to ask for?|||What I'd do is figure what the minimum price that you can sell the boat for, then add a fair commission, say 5%, then set a higher asking price. I'd do this for every boat in inventory. Then agree on a split if you get the asking price, like 40-60 to the owner. That gives you a minimum amount and an incentive to get the best price for the other guy.|||25% of profit or 2.5% of sale price