phpBB marketplace — a site-wide discovery feed covering every forum plus five per-forum feeds for replies and price drops.

P2P marketplace app — full live catalog mirrored from its sitemap; schema.org data on every listing.

Reused commercial goods on consignment — full catalog mirrored from the pages' inlined product JSON.

Booth-based kids' flea market — watcher terms polled against the platform's item-search JSON (Reykjavík store).

General classifieds — watched categories plus watcher terms searched server-side as a recall channel.