Sydney's Duplicate Image Problem: How the City Stacks Up Against London, Singapore and New York

Sydney's property and public records sector is grappling with a growing duplicate image problem, one that costs agencies time, muddies data integrity and, in some cases, has led buyers to inspect the wrong home. The issue sits at the intersection of the city's overheated housing market and the digital infrastructure supporting it — and, compared with peer cities, Sydney is behind.

The problem is not trivial. Duplicate images in property listings — where the same photograph is recycled across multiple addresses, or a stock image is substituted for an actual property — distort how buyers assess homes. In a market where a semi-detached in Marrickville or a two-bedroom in Parramatta's Phillip Street corridor can attract dozens of competing offers in a single weekend, accurate visual data matters. Buyer advocacy groups have raised the issue with NSW Fair Trading on multiple occasions over the past three years, arguing that misleading listing images contribute to the broader transparency failures plaguing the state's real estate sector.

What Sydney Is Actually Doing

The NSW Valuer General's office, which maintains the state's land values database used to calculate council rates, acknowledged in its 2025 annual report that image deduplication across its digital property records was an ongoing technical project. The office did not specify a completion date. Meanwhile, the City of Sydney Council, whose local government area covers the CBD and inner suburbs from Waterloo to Pyrmont, has been expanding its open data portal — but image-level deduplication within that system remains at early stages, according to published project documentation on data.cityofsydney.nsw.gov.au.

Domain, the ASX-listed real estate platform with deep roots in the Sydney market, has used automated image matching tools since at least 2022 to flag suspected duplicates across listings on its platform. The company has not published public figures on the rate of duplicates detected or removed. REA Group, operator of realestate.com.au, runs a similar internal review process but likewise does not publish granular data on duplicate removal rates in Australian cities.

The State Library of NSW's digital collections team, based on Macquarie Street in the CBD, deals with the issue from a heritage angle. The library's digitisation program — which has run continuously since the early 2000s — includes deduplication workflows to prevent the same historical photograph from appearing under multiple catalogue entries. Librarians there have developed batch-processing tools adapted from open-source software, and the library has shared that methodology with counterparts at the State Records Authority in Kingswood, western Sydney.

London, Singapore and New York Are Moving Faster

The contrast with comparable cities is pointed. Transport for London integrated automated image deduplication into its open data infrastructure in 2023 as part of a broader data quality framework, according to published documentation from the Greater London Authority. Singapore's Urban Redevelopment Authority mandated standardised, verified listing images for all HDB (Housing & Development Board) resale properties from January 2024, a measure that eliminated duplicate listing images from the national database by the end of that year, the URA stated in its 2024 annual report. New York City's Department of City Planning embedded image hash-matching into its PLUTO property dataset update cycle in late 2022.

Sydney, by contrast, has no single coordinating body overseeing image data quality across property records, council systems and commercial platforms. Responsibility is split between NSW Fair Trading, the Valuer General, individual councils, and private platforms — and none of those bodies currently report publicly on deduplication metrics.

That fragmentation is partly structural. Australia's federated system means that the kind of top-down mandate Singapore or London can issue requires either federal intervention or voluntary coordination between state agencies and private platforms. With the NSW Labor government focused on housing supply — Premier Chris Minns told delegates at the party's state conference this weekend that the political path ahead is steep — administrative data quality is not commanding the same political attention.

For now, buyers in Surry Hills or Blacktown inspecting a property should independently cross-reference listing images against Google Street View and request the agent's photo timestamp metadata before signing anything. Property data advocates say pushing NSW Fair Trading to publish annual deduplication compliance figures from the major platforms would be a workable first step — and one that Sydney's peer cities have already taken.