bartering/swap system php need!!

We need a bartering/trading programming. In this website, instead of forcusing on items, , we focus on a service exchange. Simple process: 1. a boy posts his offer.(ex. I can teach you how to play baseball, so please teach me how to play soccer.) 2. a girl views his offer, and if she likes it, she pushs "offer" bottun, and send message/negotiation (ex.I can teach you soccer, I am a proffessional soccer player.) 3. he can check the replied from people who had clicked "offer" ,and can check comments/negotiations from others. (he can receive this notice by e-mail and also can check these process in his personal page.) 4. he checks all people's profile, what tasks they have done, and so on in this website, and chooses only one person. Then, he clicks "accept" 5. She received an email,and both start exchanging their service. (they can check, edit, and delete internal email, offers, accepted offer, completed offer from thier personal pages.) 6. after completing the task, they must review each other. we want design and manage the website. If you have a demo/sample of Barter system scripts please let me know. It is also ok to custamize the existed scripts. We need basic scripts such as, tell a friend, register, login, personal page, simple search, advance search, "view by category",etc. -a person who checks another's post can check what other people offered like a "Get a freelance.com." -Smarty template is also ok, but we do not know much about it. -we know little about programming, so we need a great support(by email or chat). We can tell more detail when you send offer/message.