Hi,
I appreciate your interest in our themes. I would love to answer your questions.
1. Yes. You can create a website using our theme, pass it off to your client but your client cannot resell or redistribute it.
2. Yes, new owner can use and edit the theme as any other user would.
3. No, they don't have to pay anything extra to continue using the theme. But you will have to renew the license after one year if you need continued theme updates or access to our support forums.
4. No, only the user who made the purchase would get access to the support forums.
5. Yes, absolutely. We can do that.
6. Yes, you can remove our branding from front-end as well as back-end.
Hope that helps and don't hesitate to ask us any other questions you might have.