Comparable evidence sits at the heart of most residential valuations. The basic idea is straightforward: consider transactions involving similar properties, then analyse how those properties differ from the home being valued. In practice, selecting and reconciling evidence requires care because no two London homes, leases or transactions are exactly alike.
The aim is not to find the nearest sale or the highest price. It is to assemble a balanced body of evidence that reflects the market at the relevant valuation date and supports a reasoned opinion for the stated property interest and purpose.
Qualities of useful evidence
RICS guidance describes ideal comparable evidence as recent, similar, verifiable and representative of an arm’s-length market transaction. Several pieces of evidence are preferable to dependence on one result. The weight attached to each item depends on its reliability and relevance.
A sale in the same street may be less useful than one farther away if its size, tenure or condition is materially different. Conversely, an older transaction in the same building may reveal something important about layout or leasehold demand when adjusted for market movement.
Differences the valuer considers
The valuer investigates characteristics that market participants appear to reward or discount. Adjustments are evidence-led professional judgements; they are not necessarily fixed amounts that apply to every property.
- Micro-location, outlook, noise and access
- Floor area, layout, bedrooms and outside space
- Freehold or leasehold tenure and relevant lease terms
- Condition, specification, age and alterations
- Parking, floor level, lift access and building amenities
- Transaction date, incentives and any unusual purchaser motivation
Published data has limits
HM Land Registry Price Paid Data is an important public source, but registration takes time and the dataset does not reveal every fact behind a transaction. It excludes some transactions and cannot by itself explain condition, lease detail, incentives or whether a sale involved unusual circumstances.
Asking prices and online listings can help identify a property’s presentation and market competition, but an asking price is not proof of an agreed or completed price. Evidence may be checked against multiple sources and, where possible, verified.
Reconciling the evidence
After analysing similarities and differences, the valuer decides which evidence deserves most weight. A range may emerge before the final opinion is selected. Where evidence is limited, the report should communicate important uncertainty, assumptions or limitations rather than implying false precision.
The conclusion applies to the stated date and purpose. Later sales may be informative but do not automatically establish what the property was worth at the earlier valuation date. The report should explain any evidence shortage that materially affects confidence.
Advice for your property
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Authoritative sources and further reading
The guide is general information, not property-specific, structural, legal, tax or financial advice. Source pages can change; consult the relevant professional for your circumstances.