Sub-roles and role purchase I developed a site using Drupal 7 and the Ubercart module, where I sell user roles. I have sub-roles like the following.


Producer


Co-producer  
Ex-producer



How can I manage this? Is there any sub-role concept existing or manageable with category name in Ubercart?
I think you are looking for something like Sub Users module to set relation between two user types.

I also sell membership with help of Drupal Commerce in D7 &amp; I have used same thing but some modified version of the module which you can find at my given link here --

https://drupal.org/node/2049703

I sell membership to have some access &amp; sometimes I create a usertype who has got authority to create more sub user under him to have access allowed for that particular membership type.