If you’ve been to a property auction in Australia, you’ve probably experienced the frustration: the house that was “expected” to sell for $1.2 million suddenly goes under the hammer for $1.6 million or more. The practice is known as underquoting, and despite repeated crackdowns from regulators, it remains one of the industry’s most persistent and controversial problems.

Now, one frustrated Sydneysider has decided to fight back with data.

Enter realestats.org

A new tool, realestats.org, created by a developer named Sergio, is shining a light on agents where they're associated with property sales that often have a gulf between what they were quoted at and what they actually sold for. The site tracks the prices agents quote in their campaign material and compares them with the eventual sale price. Where there’s a gap, associated agents are put onto a leaderboard of sorts.

Sergio explains his motivation simply:

“Frustrated by the lack of transparency and data in the Sydney real estate market, I’ve set out to open access to data and statistics through a simple real estate tracking website. Currently starting small, and looking to expand data richness and functionality.”

The project seemingly started life as a straightforward affordability tracker, charting suburb price movements and giving buyers a bird’s-eye view of trends. But the pivot to exposing underquoting marks a novel escalation. It’s no longer just about monitoring affordability; it’s about holding the industry to account.

The fine print

RealEstats is careful to stress that its rankings are modelled estimates, not statements of fact. The site collects data manually from publicly available sources, which means the numbers are always partial, subject to gaps, delays, and errors.

The data isn’t intended to cover every agent in Sydney, nor to provide a complete picture of the performance or competence of those who are included. Omission doesn’t mean an agent is blameless, and inclusion doesn’t mean they’re guilty of wrongdoing. The figures are published as opinions for general information only—not as financial, legal, or professional advice.

Methodology at a glance

• Scope: Sydney metropolitan sales only, where both a price guide and final sale price are available.

• Thresholds: Agents must have at least five recorded sales to be ranked, and prices must be above $10,000.

• Estimation error: The core metric is the difference between the guide and the sale price, expressed as a percentage. Smaller numbers mean more accurate estimates.

• Bias check: The system flags whether an agent consistently under- or over-quotes.

• Quality controls: Outliers (greater than ±50%), missing data, or sales more than 18 months after listing are excluded to keep results meaningful.

 

Ultimately, RealEstats doesn’t claim to deliver a definitive judgment on any individual agent. Instead, it offers a snapshot of how closely an agent’s quoted guides line up with actual sale results, giving buyers one more layer of transparency in a murky market.

Why underquoting matters

On the surface, underquoting might look like clever marketing—lure more buyers to an auction by advertising a property at a price well below what the vendor will accept. But for homebuyers, particularly first-timers, it’s demoralising and costly. Many spend thousands on legal checks and building inspections, only to discover the property was never realistically within reach.

The broader issue is trust. When guide prices don’t reflect reality, confidence in the real estate process erodes. It creates a perception that buyers can't participate in the tricky real estate game, leaving them disillusioned and sellers caught in a reputational crossfire.

In most states, agents are legally required to provide an honest estimate of what a property is likely to fetch. They cannot advertise a property below the seller’s reserve price or below their own internal assessment of value. Breaches carry fines in the tens of thousands, and regulators like Fair Trading NSW and Consumer Affairs Victoria regularly investigate suspicious campaigns.

But regulators can only act once complaints are made.

Real estate bodies often argue that price prediction is difficult, especially in hot suburbs where auctions can spiral higher. And it’s true: competitive bidding sometimes pushes results far beyond expectations. But consumer groups argue that doesn’t excuse agents from advertising unrealistically low guides.

By calling out these price gulfs, realestats.org adds a new layer of information for buyers. Whether the industry takes notice remains to be seen, but for buyers burned by the auction merry-go-round, it’s another tool to help level the playing field.