CheckValueAccuracy and method
What the market value range means, how it is produced and where its limits are – without marketing claims.
What the range means
The market value range is a 68 % interval under the FSD convention (forecast standard deviation) derived from regional back-tests; the number, age and distance of comparables set the confidence level. Where data are thin, the report is automatically downgraded to “indicative only” and says so.
In practice: in roughly two out of three cases the actual sale price falls inside the range; the point value is its centre. That is why we always state range, point value and confidence level – never a single “value”.
| Confidence level | Meaning |
|---|---|
| high | Many recent comparable sales nearby, complete facts, ordinary property type. |
| medium | Enough comparables, but older, farther away or adjusted (size, year, condition). |
| limited | Few comparables or an unusual property – the range is wider and the report is marked “indicative only”. |
How the figure is produced
- Comparable sales: prices of similar properties from each country's register and market data, weighted by distance, age and similarity.
- Official price indices: comparables from earlier years are brought to today with the regional price index.
- Adjustments: size, year built, condition, floor, energy class, fittings and location factors (noise, natural hazards, infrastructure) – every step is visible in the adjustment table of the report.
- Photos: optional; they help judge the condition realistically. They do not replace a viewing.
- AI model: checks plausibility, writes the texts and assigns sources. It does not invent numbers – every figure in the report has a source with retrieval date.
- Rental value: derived from rent indices, asking rents and local yields; a band rather than a point value.
What lowers accuracy
- Few or old comparable sales (rural locations, rare property types).
- Unusual properties: villas, listed buildings, commercial shares, building land, properties with a renovation backlog.
- Incomplete or estimated facts – above all floor area and condition.
- Market turning points: indices reflect trend breaks only with a delay.
- Rights and encumbrances (rights of residence, leasehold, easements) that no model can read from data.
Measured accuracy
Per market we publish the median absolute error (deviation between point value and actual sale price) as soon as at least 30 reports with a known sale price exist. Until then we deliberately state no percentage – and no “± 10 %”.
| Market | Reports with known sale price | Median absolute error |
|---|---|---|
| Austria | not yet published (under 30) | – |
| Germany | not yet published (under 30) | – |
| Switzerland | not yet published (under 30) | – |
| France | not yet published (under 30) | – |
| Spain | not yet published (under 30) | – |
| Italy | not yet published (under 30) | – |
| United States | not yet published (under 30) | – |
Sold with a CheckValue report? Tell us the achieved price (info@checkvalue.net) – it enters this table anonymised.
Sources per country
| Country | Official and public sources (excerpt) |
|---|---|
| Austria | Statistik Austria · OeNB · IMMOunited · HORA · Lärminfo.at · basemap.at · Energieausweis (HWB) |
| Germany | Kaufpreissammlung Berlin · Destatis · BORIS Berlin · Berliner Mietspiegel · Umweltatlas Berlin · Geoportal Berlin |
| Switzerland | Statistisches Amt Kanton Zürich · BFS · swisstopo · BAFU · GEAK · Wüest Partner |
| France | DVF · DGFiP · INSEE · Notaires · OLAP · Géorisques · Bruitparif · IGN · ADEME |
| Spain | Colegio de Registradores · INE · Catastro · SNCZI · MITECO · Ayuntamiento de Madrid · IGN · PNOA |
| Italy | OMI · Agenzia delle Entrate · ISTAT · Catasto · ISPRA · Roma Capitale · Regione Lazio · ENEA |
| United States | LA County Assessor · FHFA HPI · U.S. Census · FEMA NFHL · HUD · USGS |
Not an appraisal
The report is guidance. It is not a certified valuation, not a mortgage valuation and not an appraisal performed by a licensed or certified appraiser – and not suitable for lenders, courts, authorities or tax purposes. More in the help centre and the terms.