Customer & user website

Hi. This is my project. For the record I am myself a software developer so I will do the detailed specifications. Basically I need a website with users and customers: - Users create accounts and post some descriptions (along with some other informations) about theirs work. - The customers are not listed on the website. - The customers creates accounts and can see all the users (using some search criteria) - A customer can contact a user through the website. - Users can discuss with a customer through the website or directly by email (so having a messaging panel). - The customer does not see the full details of a user(only the description and some other informations). - A user can decide (after a first contact) to reveal his contact infos to a customer. - Messages exchanges between a customer and a user will be available - The customer can search a user, but a user will not be able to search anything. - The website will be accessible only after creating an account. For the moment I don't know how to handle the design part. Anyway I would like something light, simple. I would like to have something with fancyboxes and ajax. I'm looking for someone with strong experience that is able to propose the best ideas to do the job faster and as much as bug proof as possible. If you don't know what a 'sql injection' is, please don't to bid. Thanks. Please show me some examples of your work. Best regards.