Client control panel plug in

I have a website that allows clients to register their staff on my site.

I am looking for a plug in that will allow me to give my customers their own client area (accessible by unique username and password) that has abilities to:
change passwords
Receive private messages (emails) from admin
Dashboard of staff that are registered in our program
register staff in our program

If there is a control panel plug in out there that will do this I would love to hear about it.

Or could it be that I have to use other plugins and link them to this clients control panel?

Im really not sure how to approach this. Any help would be great.