Please suggest the best project management solution for a site like iWriter

Am working on a freelance website and desperately looking for a solution. I want to setup a site like UpWork or Fiverr except; I want to eliminate client to freelancer direct contact. So this is how it work:

  1. A client list a project on the site and pre-pays for services. The charges are predetermined by the website admin (terms of service).
  2. The project(s) is/are posted on a job board for freelancers to pick.
  3. A freelancer works on a project of their choice. It passes though a reviewer for moderation.
  4. Project is submitted to the customer.

What is the best solution for me? Please assist.

Hey There,

I have done that previously, so there is a Project Manager who is dealing with the task and not the freelancer.
Can help you further with it, feel free to email me at kostaskatsimitrou@gmail.com