Manually extend bulk license upgrades?

I’m not fully understanding how this works. I have several questions:

1. Is there a way to change the bulk upgrade license payment to a monthly payment instead of annual? Or, could I use an external payment system like 1 Shopping Cart to take payment?

1. Is there a way to manually extend bulk upgrade licenses?

2. Can the user who gets those license upgrades actually then create the sites and then apply the license?

Sorry if I’m not quite understanding how this works. I want to set up the following scenario;

1. Sell licenses to create 10, 25, 100, and 500 sites

2. let the user with the licenses create the sites on their own.

Thanks for your help.