I am not aware of any BP-specific plugins that enable such a feature. Perhaps you should make a request in the BuddyPress Features Group or offer to pay someone to build such a plugin on the BuddyPress Job Board.
I think if you find a basic but good Paypal plugin for WordPress, that’s half the battle. The API is a bit awkward to work with (in my experience).
Have you talked to the WP e-commerce guys (http://twitter.com/danmilward) about bringing e-commerce into BuddyPress as a group plugin? I saw Dan present at Wordcamp UK and he seems quite a friendly chappy.
many thanks for your comments !
Is there a chance to charge users for having a blog ?
– users with just a normal user-account: free
– users signing-up for having their own blog: have to pay a monthly or yearly fee
