IMMO BTC — apartment and house comparison methodology, 21 September 2026

Source: DGFiP open data on registered property transfers, geocoded by Etalab. Sales year: 2025; department: Alpes-Maritimes. This is IMMO BTC’s own descriptive calculation.

Selection
Records are grouped by transaction identifier (id_mutation), with exact duplicate rows removed. We retain ordinary sales (nature_mutation = Vente) involving one deed subdivision (numero_disposition) in one municipality. After deduplication, each transaction must have exactly one apartment or house row. Ancillary premises and blank premises types are allowed; commercial premises are excluded.
The price and recorded built floor area (surface_reelle_bati) must be positive. A further filter retains ratios from €500 to €25,000/m² inclusive. This removes extreme values, so the sample does not cover all sales.

Calculation
The total transaction price is divided by the dwelling’s recorded floor area for each sale. We then calculate the median of these individual ratios. The median purchase budget is calculated separately from total transaction amounts. Results are rounded to the nearest euro. Sample sizes count selected sales.
The total price may include land, a garage and other premises. Their values are not separated. Recorded floor area may differ from the Carrez measurement. The medians therefore describe the property packages sold.

Use and limitations
Comparisons should account for what is included in the sale, floor area, condition and precise location. The data do not adequately describe refurbishment, views, noise or condition at the time of sale. The medians are not adjusted for these characteristics. Differences across cities or years may reflect changes in the mix of properties sold. This is neither a constant-quality notarial price index nor a valuation of a specific property.
Only aggregates are published, without individual sales, addresses or information about the parties.

DGFiP / Etalab — Licence Ouverte 2.0
https://files.data.gouv.fr/geo-dvf/latest/csv/2025/departements/06.csv.gz
Retrieved: 2026-09-21
SHA-256: 4bd72468e8ca00ff99e5774730faf2cc9339c94a19b8c6db8cb95255370d07f0

2024–2025 history: the same selection is applied to 2024. Medians reflect the mix of sales without quality adjustment. 2024 sample sizes, apartments/houses: Nice 6,352/208; Cannes 2,151/70; Antibes 1,756/136; Cagnes-sur-Mer 728/99.
https://files.data.gouv.fr/geo-dvf/latest/csv/2024/departements/06.csv.gz
SHA-256: 531cff97a02ed5a80b6c0b5233ad5e0c394a7537b6854c91f0471fbc7a0d31f7