Weddingbee boards

I am working on a work related assignment and wanted to know if anyone could maybe help. 

We need to develop a community with threads and posts like WB has.  In fact, we love the WB layout but cannot pay for developers, etc.  We do have hosting capabilities. 

Here are some of the requirements we will need:

• Manager or Owner rights versus Member rights
• Closed access - only invited members can join
• Private content - only members can view content
• Managers/Owners can post documents, etc but members cannot. 
• Archive capabilites.  We need to be able to provide the content upon request if necessary. 
• Multiple board categories.  Similar to the dress boards, the fitness boards, etc.  and then multiple threads within that board.
• Poll capabilities - just like WB
• Subscribe to a topic via email

We are hoping to maybe work off an existing site that may meet these criteria but we just aren't sure who to go to.  GoogleGroups seems that it may have most of the features but maybe not all.  They are 100% free so that would be great.

Any suggestions or thoughts with how to go about this?

is quickplace an option? it's not perfect, but great for sharing documents and setting member/owner rights.