Functionality
How a Property Search Engine Works
The difference to the portal is structural: A portal (ImmobilienScout24, Immowelt, Immonet) sells advertisement places and shows its own portfolio. One Property search engine On the other hand, it aggregates offers from many sources – portals, brokerage sites, partly newspaper ads – and links to the original advertisement. Well-known representatives of this genus work like flight meta-searches: one query, many sources, one result stream.
Technically, this is done via feeds and crawlers: the search engine reads advertisements, deduplicates (the same property often appears on several portals) and normalizes the data for filters and notifications. Quality and completeness depend on the sources – those who are not read in are missing; what is listed twice is not always neatly brought together.
For searchers, this means: The meta-search is a Radar amplifiers – wider than any individual portal, but neither fully nor editorially reviewed.