AVM Market Value API

aangemaakt op 27/08/2024

The Market Value API uses ImmoParse's Automated Valuation Model (AVM) to give an accurate market value indication for residential properties.

Request parameters

The API support two modes:

  • in strict mode most parameters are mandatory (this is the default mode)
  • in flexible mode only the address and subtype are mandatory, but the confidence of the result will vary based on the number of provided parameters

Address and subtype are always mandatory. The address does not have to be normalized, the AVM will try to normalize the address, but especially for apartments a correct address with the correct bus number can make a difference.

The following subtypes are currently supported:

  • 1: House
  • 2: Piano nobile
  • 3: Bungalow
  • 4: Mansion
  • 5: Villa
  • 11: Apartment
  • 12: Studio
  • 13: Loft
  • 14: Duplex apartment
  • 15: Penthouse

Strict mode

In strict mode, the following parameters are mandatory for all subtypes:

  • liv_area: total livable area in m²
  • bedrooms: number of bedrooms
  • epc: energy score in kWh/m²year
  • condition: the overall condition of the property (bad, medium, good or excellent)
  • finishing: the finishing of the property (basic, good or luxurious)

For houses (subtypes 1-5), the following additional parameters are mandatory:

  • tot_area: total area for the plot (parcel) in m²
  • faces: the amount of faces a property has (typically 2 for closed, 3 for half-open or 4 for open)

For apartments (subtypes 11-15), the following additional parameters are mandatory:

  • garden: the size of the private garden in m²
  • terrace: the size of the private terrace in m²

These parameters are mostly relevant for penthouses or other special types of apartments and can be passed as 0 most of the time.

Flexible mode

In flexible mode, only the address and subtype are mandatory. The AVM will try to find relevant data for the given address in our database, but this information is not guaranteed to be 100% accurate or up-to-date. The found information is returned in the result. If the parameters defined for strict mode are not supplied and not found in our database, the confidence for the valuation result will be low.

Condition and finishing

The parameters condition and finishing are very important for giving an accurate valuation.

Condition describes the general condition of a property:

  • bad: structural renovation needed (eg. energy related renovations)
  • medium: some small renovations need (eg. painting, cleanup)
  • good: no renovations needed, but not new
  • excellent: new or as good as new

Finishing describes how a property is finished:

  • basic: basic materials, techniques and decoration (e.g. ceramic floor tile in standard format, laminate floor, solid core floor, painting doors, basic lighting and electrical installation, standard furniture and appliances for kitchen and bathroom, ...)
  • good: sustainable and contemporary materials, techniques and decoration (e.g. full ceramic floor tile, multi-layer parquet or ceramic parquet, composite and ceramic, veneer wood, lacquered interior doors, LED lighting, home automation, custom kitchen, ...)
  • luxurious: luxurious materials, high-quality techniques and refined decoration (e.g. marble, granite, hard stone, hardwood, solid wood, solid carpet, gold hardware, alarm system with video surveillance, indoor and/or outdoor lighting according to a lighting plan, professional kitchen appliances, custom-made furniture for a kitchen, bathroom, dressing room, living room, ...)

Other parameters

There are many other parameters defined in the developer documentation, providing them can help improve the accuracy of the valuation.

Example request

{ "validation": "strict", "property": { "address": { "street_number": "Jasmijnenstraat 2", "zipcode": 8870 }, "characteristics": { "subtype": 1, "liv_area": 180, "bedrooms": 4, "epc": 440, "condition": "good", "finishing": "basic", "tot_area": 336, "faces": 3 } } }

Result

The result for the above example can look like this: { "address": "Jasmijnenstraat 2 - 8870 Izegem", "confidence": 3, "market_value": 280000, "property": { "bathrooms": null, "bedrooms": 4, "category_id": 1, "condition": "good", "epc": 440, "faces": 3, "finishing": "basic", "is_typical": true, "is_typical_warnings": null, "liv_area": 180, "subtype_id": 1, "tot_area": 336, "year": null } }

The estimated market value for the property is € 280.000, with a high confidence. The property is found to be "typical" and there are no warnings.

If we would use 100 for livArea in this request, the output would look different:

{ "address": "Jasmijnenstraat 2 - 8870 Izegem", "confidence": 2, "market_value": 231000, "property": { "bathrooms": null, "bedrooms": 4, "category_id": 1, "condition": "good", "epc": 440, "faces": 3, "finishing": "basic", "is_typical": false, "is_typical_warnings": [ { "code": "PARAM_TOO_LOW", "msg": "unusually low liv_area for this subtype", "param": "liv_area", "translated_msg": "ongewoon lage %s voor dit type pand", "translated_param": "vloeroppervlakte" } ], "liv_area": 100, "subtype_id": 1, "tot_area": 336, "year": null } }

Now the AVM describes the property as atypical, with the primary reason being that the livable area is much smaller then similar properties in the neighbourhood. This also drops the confidence from 3 (high) to 2 (medium).

Confidence

The confidence score for a AVM market value result can be:

  • 1: low
  • 2: medium
  • 3: high

The score depends on the number of parameters that are provided (giving more parameters can improve the score), if the property is typical or atypical (as provided in the result) and if there is enough data available in our database in the neighborhood of the property.