Seller Signals
Prepared for Noble Estates · The Clarion Portfolio

Finding the houses in Clapham and Wandsworth most likely to sell next

You win most of the valuations you attend. This proof of concept is about being invited to more of them for houses: using public data to show where, across your patch, house owners are most likely to sell in the coming months, so marketing and negotiator time go where they count.

Proof of concept, version 0.3 Public data only No personal data, no addresses Houses only
Your patch in numbers

About 1,000 houses change hands here every year

House sales by year and type

Standard market sales of houses in SW4, SW11, SW12 and SW18

Show as a table

HM Land Registry Price Paid Data, category A sales. The latest year is partial because sales are registered weeks or months after completion.

Median house price

Terraced houses, and semi-detached and detached houses together, by year of completion

Show as a table

HM Land Registry Price Paid Data. Medians of recorded prices, not adjusted for inflation or the mix of houses sold.

Houses in the four districts

HM Land Registry Price Paid Data. District is the first half of the postcode; the patch boundary is assumed and still to be confirmed with Noble.

Mortgage rates since 2010

Bank Rate and quoted fixed rates at 75% loan to value

Show as a table

Bank of England statistical database: IUMBEDR, IUMBV34, IUMBV42. Month-end values.

How long people stay

Years since the house last sold

Show as a table

HM Land Registry Price Paid Data. Earlier sales are found by exact address match within Price Paid Data back to 1995, so holds longer than about 30 years cannot be seen, and some repeat sales are missed where an address was recorded differently.

What signals a sale

Houses here are likeliest to sell four to ten years after they were bought

The moving cycle

Share of houses that sold in the following 4 to 16 months, by years since they were last bought

Show as a table

Signals in the public record

How much likelier than an average house in the patch to sell in the following 4 to 16 months

Show as a table

HM Land Registry Price Paid Data and the EPC register, every quarter in the period, scored using only what was known at the time. A single signal on its own; the model combines them.

Where the next sales are

Where the next house sales are likely to come from

Show as a table

Model scores from the latest scoring run. Street names: OS Open Names, matched to hexagons by location only. EPC register (domestic certificates, open fields) placed with OS Open UPRN coordinates. A home counts as a house when its latest certificate describes a house or bungalow. Borough outlines: ONS. Each hexagon is about 0.1 km².

Houses put on the market and houses sold, quarter by quarter

Two counts for the patch on the same timeline. Certificates are lodged when a house is put on the market; completions follow some months later.

Show as a table

EPC register and HM Land Registry Price Paid Data. Completions stop where registration is still incomplete. The working tool will link certificates to sales home by home to measure the typical lead time; this chart does not claim one.

Would it have worked?

Score every house, mail the top of the list, then check who sold

The real test replays history. The model scores every house as it stood on a past date, using only what was known then. We then compare its list with the houses that actually sold over the following months.

Illustrative · simulated neighbourhood, not your patch

How a replay works, on invented data. The measured results above come from ranking individual houses in your patch; this simplified picture groups them into hexagons to show the idea.

Mailing houses at random reaches sellers in proportion to the share mailed: 10% of houses, about 10% of sellers. The gap between the two is the model's lift, and it is what lowers the cost of each valuation.

Cost per valuation

What lift is worth in valuations booked

Put in your own campaign figures. The lift is the number the backtest measures on houses in your patch; propensity models of this kind typically find two to three times the base rate in the top tenth of houses.

Every input is an assumption to replace with your own figures. Nothing here is a forecast.

Why an area scores highly

Every score comes with its reasons, in plain words

The model explains every score with the factors that push it up, worded from a short, reviewed list. Negotiators can see why a street is on the list, and the reasons suggest what to say.

Why the top-scoring houses score highly

Each house carries up to three reasons. Wording that includes a house's own figure (years owned, rooms, gain) is grouped under its rule. Only reasons shared by at least 25 houses are shown.

Proving it in your patch

A fair test: target some streets, hold others back

History shows the model finds sellers. Whether contacting them wins Noble more instructions can only be shown live. The tool sets up a controlled test so the answer is not a matter of opinion.

  1. Pick

    Take the highest-scoring streets with at least 25 houses, and sort them into five bands by score.

  2. Split by chance

    In each band, a random half is held back: no targeted outreach for the length of the test. The split is recorded and cannot be changed.

  3. Log

    Every mailing goes into an outreach log, and every valuation request into a results log, with its source and whether it became an appointment and an instruction.

  4. Compare

    Valuation requests per 1,000 houses in targeted and held-back streets, quarter by quarter, with a confidence range.

An honest caveat: valuation requests are rare, so at one agency's volumes a test takes about a year to show even a large effect. We add faster measures alongside: a separate phone number or QR code for each group's mailings, and Noble's share of sales by street, which every sale in the public record eventually reveals.

How it works

From public records to a ranked list of areas

  1. Gather

    Every recorded sale since 1995, every energy certificate since 2008, local price indices and mortgage rates.

  2. Link

    Match sales and certificates to each home, so its history (how long it has been held, what has changed) is visible.

  3. Learn

    Train on houses across Greater London, where there are over a million house sales to learn from, then test on your patch.

  4. Test

    Replay past years: score houses as they stood, and check how many of the later sellers were near the top.

  5. Plan

    Roll house scores up to areas, rank them, and measure results with a controlled test once outreach begins.

Data, limits and disclaimers

What this page is, and what it is not

Status

A proof of concept prepared by The Clarion Portfolio Ltd for discussion with Noble Estates. Noble has not commissioned this work. It covers houses (terraced, semi-detached and detached); flats are left out. Market figures, the moving cycle, the signals, the map of likely sales, the backtest and the reasons are real, computed using only what was known at each date. The animated replay uses invented data and is marked as such; the calculator's cost and response inputs are assumptions.

No personal data

Nothing here identifies a home or a person. Figures are for the whole patch, for postcode districts, or for hexagons of about 0.1 km² that each contain at least 25 houses; smaller hexagons are left out. No names, addresses, postcodes or property references appear.

Limits

Past sales do not guarantee future ones. Scores are chances, not certainties: most high-scoring houses will not sell in any one year. Energy certificates cover most but not all houses, so houses that have never been certified, which are often the longest-held, are undercounted. The patch boundary is an assumption. Results from the historical test will vary year to year, and the patch is small enough that area-level figures are noisy.

This page is not legal, financial or investment advice.

Sources and attribution

Contains HM Land Registry data © Crown copyright and database right 2021. This data is licensed under the Open Government Licence v3.0.

Energy Performance of Buildings Register, Ministry of Housing, Communities and Local Government, open fields only, licensed under the Open Government Licence v3.0.

Contains OS data © Crown copyright and database right 2026 (OS Open UPRN).

Source: Office for National Statistics, licensed under the Open Government Licence v3.0 (borough boundaries). Contains OS data © Crown copyright and database right 2026.

Source: Bank of England, licensed under the Open Government Licence v3.0.