Tip User Posts

Hello every one!

I am looking to have some one create a function on my site.
PHP, on WoWonder.

I am looking for some one to create the ability for users, to be able to tip other users Posts/Pics/Videos.

I want all payments to go through the site, where the users will get paid out every $20 earned, while the site takes commission.

I am looking to spend $50 on this project.

Thank you!