Search second-hand listings on Marktplaats or 2dehands with filters for category, price range, condition, recency and distance from a postal code.

Fetch the full advertisement: complete description, all images, view and favorite counts, listing age, seller and item attributes.

Look up a seller's trust signals: verified bank account / identity / phone number, review score and number of reviews.

Browse the category tree (shared by marktplaats.nl and 2dehands.be) to find names/ids for search_listings' category and subcategory filters.

Poll for listings placed after a given moment (newest first, paid promotions filtered out). Stateless: store the returned 'cursor' and pass it as 'since' on the next call to only see genuinely new listings.