Platform sources and limitations

1. What the demonstration presents

The platform brings together Luxembourg public property statistics and geographic reference data. It also offers a contribution area for members and experimental search tools. Publicly accessible comparables are fictional examples, labelled accordingly. They do not describe real transactions.

Aggregate statistics provide market context. They are not sufficient to determine the value of an individual property. References entered by members remain contributions that need checking; their presence on the platform does not constitute certification by LPVI or TEGOVA.

2. Sources and periods actually loaded

• Apartment sale prices. Observatoire de l'Habitat data distinguishes existing apartments from sales before completion (VEFA). The database contains 2025 and the April 2025–March 2026 window. Price series before 2025 are not loaded in this version. View the dataset and its publications.
• Adjusted prices excluding ancillary spaces. A separate series, loaded for April 2025–March 2026, deducts a contribution from ancillary spaces estimated by the producer's statistical model. The main map shows standard prices: these two measures must not be confused. View the producer's method and data.
• Advertised rents. Apartment series cover 2009–2025 and the April 2025–March 2026 window. House coverage is limited to four municipal observations in that latest window. These are asking rents in advertisements, not rents recorded in signed leases. View the advertised-rent dataset.
• Geography and addresses. The loaded reference data contains 100 municipalities, 24 Luxembourg City districts and 178,815 addresses, according to the count on 9 September 2026. Municipal boundaries and addresses come from Administration du cadastre et de la topographie reference data. These counts describe the database loaded on that date.

3. Reading the figures and data processing

Periods, property categories and units must be compared on an equivalent basis. For apartment sales, the producer's usable area is based on the vertical cadastre, excluding garages and cellars; it must not automatically be equated with other area definitions used in a valuation. Observatoire de l'Habitat sale-price methodology.

• Producers apply publication thresholds: at least 10 transactions for prices and 30 advertisements for rents. A missing value may also reflect an unavailable series or a missing geographic match. The platform does not reconstruct missing values.
• For sale-price ranges, the producer's method excludes the lowest 5% and highest 5% of prices. This rule concerns the range boundaries; it is not a new calculation performed by LPVI.
• Municipality names are matched to geographic reference data. Some historical rent observations do not correspond to today's municipalities: they remain in the database but are not shown on the current municipal map. They are not arbitrarily reassigned after a merger.
• Geometries are stored in LUREF (EPSG:2169) and converted for web display. Municipal boundary files are imported from WGS84; addresses use LUREF coordinates on input.
• The extraction register records the date, file fingerprint and row count, among other information. Traceability is still partial: the original file URL is not yet recorded for every extraction, and individual addresses or municipalities are not each linked to the register. Producers' dataset pages remain the reference for their methods and reuse conditions.

Base maps and thematic layers provide context. They do not replace consultation of applicable regulatory documents with the competent authorities.

4. Member contributions and human review

An administrator assigns a personal account and role to each authorised member. Contributions are linked to their author and can be revised and submitted for validation. This attribution is neither a certified electronic signature nor automatic verification of the author's professional qualifications.

The form distinguishes, among other things, property type, date, amount, different area definitions, VAT treatment and the declared origin of the information. Some fields remain optional or accept unknown values; free-text notes are possible. Those responsible for validation must review consistency and the quality of supporting documents.

Access depends on the member's active status and role, with consultation and export limits. No minimum number of contributions is currently required for access. The platform does not vary geographic precision by reader.

5. Artificial intelligence assistance

Natural-language search turns a question into structured filters checked by the server. References are then retrieved from the database with their identifiers. This mechanism does not guarantee the accuracy of every sentence produced by AI and does not provide an expert valuation or automatic estimate.

Search questions are sent to the configured AI provider. Successful searches are logged with their filters and result identifiers. This log is not a comprehensive record of all exchanges, errors or drafting operations. Any proposed text requires human review.

CSV or Excel imports are processed without AI. AI analysis of PDF documents is disabled in the demonstration; enabling it would require service configuration and the user's consent for the document concerned. Provider terms, data retention and permitted uses must be examined before sending any confidential content.

6. Administration and handover

Several administrators can manage access and hand over responsibilities. A safeguard prevents removal of the last active administrator linked to an account. Some sections have publishing tools; other pages still require changes by the person maintaining the site.

Handover of hosting accounts, code, the domain name and sending services must still be organised with the association. Site permissions do not, by themselves, transfer these accounts or legal ownership of data. Data processing terms are set out in the legal information and will need to be adapted to the intended operational uses.