Discussion forum with some extra functions

I would like to build a discussion forum with some standard functionalities and some special ones. Existing bulletin board engines can be used as inspiration, but I want this software to be started from scratch since there will be a lot more functions in the upcoming phases of development, and the system should be extendable and scalable. Standard discussion forum functionalities, for example: - create a new topic (idea) - comment on a topic (idea) and reply to a comment - search the forum - send a private message to a user - standard user profile creation - standard moderating functions (for administrator) Extra functionalities, for example: - team creation: join a topic/idea (become a team member candidate) - accept/reject a team member candidate - finish the team creation and start the project As software architect I would be responsible for the analysis and design (and eventually help with programming too), but I need an experienced PHP developer to do the coding. The best would be to use a modern MVC framework like Yii or Laravel 5. Since this is only a small part of the whole software to be created, there is a good chance for long term cooperation in case of success.