Setup Configuration | Membership multisite access


I am setting up a new site that has some advanced configuration that I am struggling to get correct. I am doing a fresh install of wordpress on my server so make sure everything is up to date.

What I am trying to do is structure a network of users and sites using multisite and buddy press.

The main site will be the landing page where users can register for free. From here someone can also choose to set up a private sub site. These sub sites are where the users will spend all of their time after registration.

Each sub site needs to be private to users on entire network unless they are a registered user of that site. Each needs the ability to request access from the admin to join any sub site. Each users will be a part of a few of these sites.

It is a network of smaller social networks that can overlap with permission.

What plugins should I use to get this functionality and how should I configure them to get it to work correctly?