Build a Facebook look-alike site Social networking website

If you please give me a rough estimate of how much it will cost to develop for me a social networking website with features that cover some of the standard aspects of any social networking site--a Facebook look-alike site using LAMP (Linux, Apache, Mysql, PHP) platform. It would work best with a programmer with a CMS platform that was designed to meet 75% or more of most clients\\\' functional requirements and easily customizable to close the gap to 100%. Personally, I am not looking at a customized website for now. I also need to know how long it will take to complete the work. \r\n\\\"Social networks like Facebook, Twitter, [login to view URL] and Myspace are websites for connectivity between individuals (or organizations) based on various factors like common likes and dislikes, friendship, financial exchange, sexual relations, beliefs, or knowledge.\\\"\r\nThe features may include:\r\nLanding Page; User Registration; Login, Logout, Lost Password; Activity Feeds; Liking, Commenting, Sharing; Member Profile; Account Settings, Privacy; Member Wall; Messaging/ Email; Instant Message; Notifications; Friends; Invite; Member Search By Name, By Email, By School, By City or Zip Code, By Interests, By Keyword; Content Search; Admin Create Additional Pages; Admin Roles; Membership Plans; Advanced Privacy Settings; Photos & Video Sharing; Sub-groups; Monetization--Targeted Advertising; Domain Name\r\n