Using Pro-Sites plugin, is it possible for users to manage more than one site?

We would like to allow our users to create and manage more than one wordpress site. For example, this will allow them to have one for hobbies, one for work etc.

Is it possible to manage more than one wordpress site using the same account in Pro-Sites? For instance, they might sign up for the plan which gives them up to 3 sites to create and manage through the one interface. The billing would also come under the same payment plan.

If i'm missing any information you require to answer the questions properly please let me know and I will promptly update.