PHP / CMS Development of existing site - repost

Hello. I have an existing site using a CMS and PHP developed areas to provide a customer facing user experience. The website allows people to register and login to their own accounts and use logged in areas to view their own details and specific information about the account. There is also a PHP based Admin area which is designed to oversee the entire group of users and view the data of them collectively. There are various pages to view specific product information, user information and statistical information. The project is to take the existing system, and make new modifications to the site in line with a new business process. We will need to add new registration areas, user detail pages, admin detail pages. All the designs are done, and in PSD format. We just need to build. I can provide more details to the right developer. Thanks