Blogging for Income

Hi Support,
I am looking to add in my membership a level for users to opt in for $$$/m to be able to post their blogs. I am running buddypress on a MU Theme. Can you tell me which plugins you would recommend I use on my http://www.useapro.net site to be able to host many blogs? I will have the potential of having hundereds to gazzillions of blogs in my different post catagories.
Blessings,
Wendy