Track add ons for enabled subs

As a user, I would like to be able to track my add-ons for subscriptions that allow them, such as BOTM or Aardvark, in the subscription view. I'd like to be able to have my renewal date charge linked to a particular month’s box on one date (ie 10/26 for November box) and then be able to attribute to that same box one or more add-ons and the add-on cost (ie +$12.99 on 11/1 fr November box) so that my total for that month's subscription includes the full cost of the box with add ons, and so that I can attribute certain books in my library to that particular month’s box.