subscriptions/installed_items/configuration
- GET subscriptions/installed_items/configuration/add_installed_items/list — This method returns the the physical goods that can be added on an existing subscription. Multiple physical goods are returned by each call
- GET subscriptions/installed_items/configuration/become_subscriber/list — This method returns the the physical goods that can be used to create a new subscription of a specific type. Multiple physical goods are returned by each call