Listing and Exclusion for a particular account represents which products are permissible or not permissible for that account in a specific timeframe for a particular business transaction.
In case of PPR, assignment of business partners, products and timeframe is done. The necessary settings for the PPR are done in the customizing.
In the newer approach Listing determines a product valid or invalid. This Listing consists of header and item. Header contains the condition technique and item contains PPR information.
With free goods you can implement quantity discount. That is, you can offer a product for free to your customer when a certain quantity of product has been ordered. This feature is also implemented using the condition technique. It could be implemented in two ways: