Membership and pro sites

I have been reading through the new membership manual and it is quite helpful, however I still have some questions.

Which is the best way to set up paying for blogs membership or pro site? I saw it looks like now you can do this with membership.

I have the payment gateway set up for pro sites will I need to also set it up for memberships? Does the membership payment override the pro sites?

Do I need a membership level to correspond to each pro site level?
or
Is it best practices to have a membership level that corresponds to each pro site level?

Or can I have one membership level and use it for several pro sites levels.

Can I have 1 singup page for non professionals and 1 for professionals? If I do have two sign up pages will it cause any confusion or problems?