# About This Research

*Category: Reference*
*Topics: cotleigh road, romford, house prices, regeneration, open data, valuation estimates*

This page explains the methodology and limitations of an independent research project about Cotleigh Road in Romford, RM7, covering its history, regeneration, and house price estimates. The project uses open data from HM Land Registry and automated valuation figures from Zoopla and Rightmove. It aims to provide a transparent and checkable record of the street's values, while being clear about the edges of the evidence and potential disagreements between sources.

## Key points

- Uses open data from HM Land Registry and automated valuation figures from Zoopla and Rightmove
- Provides a transparent and checkable record of Cotleigh Road's house prices
- Clearly states limitations and potential disagreements between sources
- Allows users to request corrections or removal of estimates for their address
- Aims to provide a useful resource for those interested in the street's history and property market

## Content

This site publishes research on one street: Cotleigh Road in Romford, RM7. It
covers the street's history, the town's history, the regeneration on its
western boundary, and what its houses are estimated to be worth.

This page explains how that is done, what it is not, and how to challenge it.

## What this site is

An independent research project about a single residential street. It is not
an estate agency, it does not sell anything, it takes no commission, and it has
no advertising. It does not introduce buyers to sellers and it does not pass
details to agents.

Nothing on it is financial advice, and nothing on it is a substitute for a
survey, a mortgage valuation, or professional advice about your own
circumstances.

## How the figures are produced

**Sale prices** are HM Land Registry Price Paid Data — the price recorded when
a property changed hands. These are facts, published as open data under the
Open Government Licence v3.0, and every page reproducing them carries the
required attribution.

**Valuation estimates** are Zoopla's and Rightmove's own automated figures. Each
one was opened on that property's own page, read, and recorded with the date it
was captured. **No estimate on this site is calculated, indexed forward or
averaged here.** Where a property has not been captured, the cell is blank
rather than filled with a derived stand-in.

That distinction exists because an earlier version of this site got it wrong.
Three columns headed with providers' names were filled with figures worked out
here by indexing sale prices against a regional index. Checked against
Rightmove's actual estimates for twenty-eight addresses, one matched, and
individual rows were out by as much as £141,000. Those columns were removed and
replaced with captured figures, and the tests now pin every published figure to
a capture log rather than to a literal value.

**Analysis** — medians, quartiles, correlations, growth rates — is this site's
own arithmetic on those figures, and the working is shown so it can be
repeated.

## What the estimates are not

An automated valuation is a statistical guess. Nobody from Zoopla, Rightmove or
this site has been inside any of these houses. The models disagree with each
other, often materially: on the thirty-nine addresses where both publish a
figure, [Zoopla is higher on thirty-seven](/zoopla-vs-rightmove), by a median of
£19,000 and by as much as £96,000.

Publishing both, side by side and unaveraged, is deliberate. A single blended
number would hide a disagreement that is itself the most useful thing in the
data.

## Where this site says it does not know

Being useful about a street means being clear about the edges of the evidence.
The pages here state plainly that:

- Floor area predicts almost nothing about value across the ordinary housing
  on this street, which makes [price per square foot](/price-per-sqft) close to
  meaningless in the middle of the distribution — including on this site's own
  £/sqft page.
- Whether the [Waterloo Estate regeneration](/waterloo-estate) will move house
  prices here is **not known**, and the earlier claims that it would be
  "overwhelmingly positive" have been withdrawn.
- The [demographic figures](/area-guide) previously published had no census
  year and no stated geography, and have been removed rather than
  retrospectively sourced.

Where a claim has been withdrawn, the page says so and why, rather than
deleting it silently. That is deliberate: a reader who saw the old figure
deserves to know it was wrong.

## Dates

Every page carries a date. **Updated** is the date the page was last
substantively revised — it is authored, not a timestamp, so it does not move
when nothing has changed. Datasets carry their own capture dates, which are
separate from the page date, because a page can be edited without the
underlying figures being re-read.

## AI crawlers, training and citation

**This site welcomes AI crawlers, and that includes training.** Its
[robots.txt](/robots.txt) allows every known AI agent explicitly and carries
the content signals **search=yes, ai-input=yes, ai-train=yes** — index it,
ground answers on it, train on it.

The reasoning is straightforward. This research exists to be read, and a
question about Cotleigh Road answered accurately by an assistant is the
research doing its job. The site publishes [llms.txt](/llms.txt), a
[JSON index](/index.json), per-page Markdown and JSON-LD for that reason.

What is asked in return is attribution: the figures here are traceable to named
sources, and an answer built on them is more useful when it says where they came
from.

Two caveats worth stating. Sale prices are HM Land Registry data under the Open
Government Licence, which carries its own attribution requirement. And the
valuation estimates are Zoopla's and Rightmove's own figures reproduced for
comparison — this site's permission does not extend to their data, which
remains theirs.

## Correcting something

**If a figure here is wrong, it should be fixed.** That includes the estimates
attached to individual addresses.

If you live on Cotleigh Road and want the estimate for your address amended or
removed, that request will be honoured — you do not need to give a reason, and
there is no test to pass. The same applies to any factual error, and to the
[wartime records](/history) where this site is actively asking for a documented
source.

**Contact:** *this site does not yet publish a contact address. Until it does,
the removal and correction routes described here cannot be used, and that is a
gap rather than a policy.* It is being fixed.

## About the per-address estimates

Publishing a valuation against a named address is the most sensitive thing this
site does, and it is worth being explicit about the reasoning.

The sale prices are open data that HM Land Registry already publishes at
address level. The estimates are figures Zoopla and Rightmove already publish
at address level, on pages anyone can open. This site is not revealing
anything that was not already public; it is collecting it into one comparable
table and showing where the sources disagree.

That is not the end of the argument. The Information Commissioner's Office has
taken the view that property price data can be personal data where other
public information makes it relatable to an individual, and HM Land Registry
disagrees; the point is unresolved. This site's position is that the public
interest in a transparent, checkable record of one street's values is
legitimate, that the information is already published elsewhere, and that
anyone who objects should be able to have their address removed on asking —
which is why the contact route above matters more than anything else on this
page.

## Related

- [Sources and references](/sources) — every dataset and document used
- [The valuation matrix](/property-market) — the per-address table itself
- [Zoopla versus Rightmove](/zoopla-vs-rightmove) — where the providers
  disagree

## Source

- Canonical URL: https://cotleighroad.com/about
- Typed record: https://cotleighroad.com/index.json