New interactive internet platform for new social enterprise

For a new social enterprise /charity I need an internet platform - the whole platform is the enterprise, as all communication and activity happens online.

I need two prices, please:
webdesign side (welcome page, one template for all other pages, registration page design)
programming - or puttting together pre-existing modules of ready made software

Details:
people need to register and pay a small registration fee via paypal, I need to approve their registration
they have access then to some files for their type of membership - there are two areas for two types of membership
I can release a limited number of files for each new member to see that only s/he can see then
there should be a chat room facility within the internet platform so two members or three can chat, and I need access to that chat as well
members working together can create a shared access controlled area in which they share information/files, just the two or three of them
skype type facility for communication within the platform

Once a provider has been selected, specific detail on the context will be released.