Member only website

What we need: We want a site like Linkedin but with restricted joining acces and of course much less functions- all members are hand picked and must be approved by the site admin team, no one can join and enter freely. We would like to use a open course CRM, something like Elgg, kickapps, xoops should be able to handle what we need. We are a startup company and will grow the site in the future but to start with a list of most of the features: - Ability to detect interpersonal relationships (by training courses, past employment, present, studies, etc). - Ability to send invitations to friends to apply to join the site (only site admin can accepted the person) - Complete profile: compulsory basic (name, region, specialty), other optional profile (training, education, full career, associations, groups ...) - Full search engine: keywords, region, specialty, industry, etc. - Possibility to link with Twitter and facebook and other site - Email and instant chat for members to connect each other - To be able to see who was viewed my own profile - Privacy settings (to be defined) - Possibility to request recommendations and skills - Show, with the contacts I have, who I can reach (degrees of separation) - To receive update on my page when someone makes a change to their profile (if my privacy settings will let me) - Possibility of incorporating a webinar tool - Payment gateway for membership fees, event fees and advance ticket buying online - To be able to use my email address to check if there's people in the network I already have as a contact - Public board to share tests, jobs, research studies, events, news: a bulletin board - Something more specific than this: an exclusive section of publications and ability to create open / closed groups to specific members. - Insert job vacancies (job postings on the board) - Possibility to create groups of interest (mini communities within the community), for example, a group of XXXX in Barcelona, a group of European XXXXXX ... - Ability to upload images / videos / files and share (links with slideshare, youtube, flickr ...?). Sharing content must be easy, and in all formats: word, excel, pdf, powerpoint... - Difference between standard users and premium users. - Possibility of introducing advertising (through banners, skyscrapers, etc) but not now down the road - To be able to create corporate pages for companies. Most of the feature are available in free open source platforms but may need a little changing and then just getting everything together and working right. Down the road after the site is live we will come back and start to do more custom work and help improve it