Community Builder (CB) is the most powerful, yet simple and free, Social Networking solution for Joomla. CB has literally hundreds of built-in features and can be extended with extra both free and commercial. We have been using CB on many sites for over a decade, it's extremely extensible, stable, and well supported, we also develop custom extensions for CB.
This job involved modifying a highly customised French Joomla/VirtueMart website for a web design agency.
Very good provider.