The present disclosure relates to methods and systems for managing how merchandise listings satisfying a search query are processed and presented to a user of a computer-based trading or e-commerce application when the listings are of heterogeneous types. Consistent with some embodiments, in response to a user-initiated search query, item listings and product listings are displayed intermingled in a set of search results pages. The item listings and product listings are positioned relative to one another, in part, based on a level of demand associated with the product listings and the item listings, where demand is measured by monitoring user-initiated activities in connection with the item and product listings.