Comparison method (méthode par comparaison)

The comparison method estimates a property from what buyers have actually paid, recently, for similar properties. The Charte de l’expertise en évaluation immobilière (the French property valuation charter) presents it as the reference approach for determining market value, because it establishes a direct link with the realities of the market. Its principle fits in one sentence: observed prices are adjusted to take account of the differences between the reference properties and the property being valued.

Its strength is its transparency: anyone can check the references and discuss the adjustments. Its limit is well known: relevance declines as the characteristics of the properties diverge, and some properties (specialised premises, investment buildings, large tracts of land) have no sufficient comparable market. The Charte then recommends an alternative method as a cross-check.

Where the rule comes from

Title III, § 2.1 of the Charte (6th edition, November 2025) sets out the principle, the sources of information (transaction prices first, asking prices with caution), the units of comparison (floor area, net income, unit) and the criteria of analysis (location, age of the transaction, obsolescence, tenancy situation). § 2.1.6 specifies that quantitative tools enrich the analysis, but that the final estimate always results from the expert’s judgement. The EVS 2025 describe the same method in their methodology section, § 6. The French tax authorities also favour it, as Title II, § 8.14 of the Charte points out.

In a valuation report

I choose the appropriate unit of comparison (price per m² of habitable area for a dwelling, per weighted m² for a shop, per hectare for farmland), assemble a sample of dated and sourced references, then present for each the adjustments applied and their reason. From this I derive a range of unit values, adopt a unit value and apply it to the area of the property, before adding or deducting the items not captured by the unit (outbuildings, surplus land, works). Where the property lends itself to it, I cross-check the result with an income method. The report ends with a range and a single figure at the valuation date.

Example

A house of 95 m² habitable area with 800 m² of land, on the outskirts of QUIMPER. Six sales of houses of 80 to 110 m² completed in the last twelve months, after adjustment, give unit values of €2,500 to €2,800 per m². I adopt €2,650 per m², that is €251,750, add €8,000 for a detached garage that the references did not have, and deduct €15,000 for the roof to be replaced, on the basis of a quote. Market value: €245,000 rounded. A cross-check by income (market rent €950 a month, capitalised at 4.6 %) gives €248,000 and supports the conclusion.

Not to be confused with

An estimate by average price per m² applies a commune-wide average without individual adjustment. The income method starts from rent rather than prices. The index method updates an old value by an index, which the Charte regards as a mere check.