Commission Based - Sell My iPhone Cases

I am selling iPhone cases through an online website and am looking for someone who is competent and confident in their internet marketing abilities. I would like to pay on a commission basis at around 5 USD per sale (this is a commission of 17% of gross revenue). As the business is quite new, traffic to the site is quite low. It is therefore safe to assume that any raise in sales and traffic will be thanks to the freelancer who is awarded this project, and thus the freelancer will be paid commission on ALL sales for the two weeks this project is expected to run.