Buyer guide

Property-data red flags

A red flag is a reason to investigate, not proof of a defect. Identity conflicts, extreme value changes, inconsistent property type, unexplained alterations and “no data” results should reduce confidence and create a clear follow-up question.

Written and reviewed by Propeteer Research TeamPublished 29 July 2026Reviewed 29 July 2026

At a glance

Identity: Flat, suffix, named building and UPRN conflicts
Market: Extreme price or £/area outliers
Coverage: No data is not the same as no risk

A reliable process

How to approach the question.

01Check whether every record belongs to the exact property.
02Compare price, type, tenure and floor area through time.
03Review unexplained planning or physical changes.
04Classify each gap as benign, unresolved or requiring professional enquiry.

Worked example

Detached, then semi-detached, then detached

This can reflect coding changes, a genuine physical change or records for two properties being merged. The system should not pick the latest label and move on; it should show the conflict and test identity.

What this does not prove

Real property changes can resemble data errors.
Public data is not a substitute for inspection.
Absence of a red flag is not assurance that no issue exists.

Method used

Start with the exact address and stable property identifiers so records for neighbouring or subdivided homes are not merged.
Separate open-data screening from formal conveyancing searches, surveys and professional opinions.
Record what was checked, when it was checked and whether the result means clear, no match, unavailable coverage or a failed connection.

Primary sources and official guidance

Price Paid DataHM Land Registry Energy Performance of Buildings DataDepartment for Levelling Up, Housing and Communities OS Open UPRNOrdnance Survey

Source scope, licensing, refresh expectations and known limitations are listed in the public data-source register.

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