Test a property value against the evidence that can support it.

Valuation starts with identity. A numbered house, a flat and a suffixed address such as 1A can share a postcode while representing different homes. Merging those records can create impossible price changes or a history that appears to switch between property types.

Where possible, Propeteer uses a stable property identifier and exact address components to keep the subject property separate. Historic transactions remain useful, but changes in description, tenure or property type are surfaced rather than silently accepted.

• Keep neighbouring and subdivided addresses separate
• Show historic type or tenure changes that need checking
• Avoid treating every postcode match as the same property

Recent sold prices provide stronger market evidence when the homes are genuinely comparable. Property type, tenure, size, location, sale date and unusual transaction characteristics all affect how much weight a sale should receive.

A larger sample is not automatically better. Older, distant or materially different sales can add context while being excluded from the central benchmark. The eligible group should be visible so the user can understand what shaped the range.

• Prioritise recent transactions of the same type and tenure
• Use floor area where it can be matched reliably
• Separate the strongest precedents from wider market context

An indexed value asks what a historic sale might be worth if it moved in line with a selected house price index. It does not know whether the property was renovated, extended, allowed to deteriorate or sold with an unusual lease.

Current comparable evidence answers a different question: what similar homes have recently sold for. The two measures can support one another, but a valuation should explain disagreement rather than average incompatible figures without judgement.

• Use HPI as market context, not an automatic valuation
• Flag long gaps since the last sale
• Allow recent comparable evidence to outweigh a weak historic anchor

Floor area helps compare homes of different sizes, but coverage is incomplete and matching can fail for flats or complex addresses. A recent sale does not guarantee that an accessible EPC record or reliable area measurement exists.

Price per square foot also reflects more than space. Layout, outdoor area, floor level, lease length, condition and micro-location can all move the achieved price. Propeteer therefore shows the underlying area and evidence count alongside the benchmark.

• Identify whether floor area is official, matched or user-provided
• Do not calculate £/sq ft when the denominator is uncertain
• Retain the reason when a comparable is excluded

Property markets contain uncertainty that a single estimate can hide. A supported range can reflect the spread of comparable sales, the age of the evidence and the degree of similarity to the subject property.

The result is an evidence-led indication, not a mortgage valuation or survey. Where the model relies on user-entered floor area, limited comparables or broad index movement, that limitation should reduce confidence and remain visible.

• Show the principal valuation anchors
• Explain caps, exclusions and material adjustments
• Avoid false precision when evidence is sparse