Thanks for the answer, Ryan.
And to sort of be repetitive,
hook uc_cart_complete_sale is where I would mess with site access?
Basically, we are charging for access to more places on our site, and putting the hook calls into this hook after payment is the way to go?
It's nothing bad, just another random b2b service. But we have some free pages, some available at one access level and a host of nodes available if you pay alot. Just the background info in case you need it.