The Address Index
Greenwich, Connecticut · Interactive market data

Greenwich Synthetic Twin Property Comparisons

Explore Greenwich Synthetic Twin estimates, earlier comparable public sales, modeled price ranges, and an interactive map.

Through September 2026
Synthetic Twin chart for 18 Azalea Terrace, which sold for $1.50M on February 10, 2026. The public-record model expected $2.35M, with a 50% likely zone of $2.07M to $2.66M and a 80% broader range of $1.91M to $2.88M. A Greenwich map locates the sale and its earlier public-sale twins.

18 Azalea Terrace sold for $1.50M, 36.1% below its $2.35M out-of-sample expectation. Its 50% likely zone is $2.07M–$2.66M; the 80% broader range is $1.91M–$2.88M. The model used 2,289 training, 501 calibration, and 501 untouched test sales; test median error was 22.4%. This is a market comparison, not an appraisal.

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What this chart measures

Synthetic Twin compares a completed Greenwich sale with earlier public-record transactions that most closely resemble it, while keeping the target sale out of its own estimate.

How to read it

The center is a pre-sale public-record expectation, not an appraisal. The likely and broad ranges are calibrated on later held-out sales, and the listed twins are adjusted to the target date.

Why it matters

Property-level context can reveal what a town-wide median cannot. The remaining gap also highlights the private features—condition, views, privacy, and terms—that public records cannot observe.

Latest reading: 18 Azalea Terrace sold for $1.50M, 36.1% below its $2.35M out-of-sample expectation. Its 50% likely zone is $2.07M–$2.66M; the 80% broader range is $1.91M–$2.88M. The model used 2,289 training, 501 calibration, and 501 untouched test sales; test median error was 22.4%. This is a market comparison, not an appraisal.

The Address Index is independent market intelligence based on public and source-linked records. It is not an appraisal, brokerage opinion, or investment recommendation.

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