# Koopsom API

## GET /mx-transaction-finder

> Returns a list of reference objects and their transaction prices.

```json
{"openapi":"3.0.3","info":{"title":"Matrixian API","version":"1.0.0"},"servers":[{"url":"https://api.matrixian.com/v1","description":"Matrixian API"}],"security":[{"BearerAuth":[]}],"components":{"securitySchemes":{"BearerAuth":{"type":"http","scheme":"bearer","bearerFormat":"{{API_KEY}}"}},"schemas":{"TransactionFinderInput":{"properties":{"postalCode":{"type":"string","title":"Postalcode","description":"Postal code"},"houseNumber":{"type":"integer","title":"Housenumber","description":"House number"},"houseLetter":{"title":"Houseletter","description":"House letter","type":"string","nullable":true},"houseNumberExt":{"title":"Housenumberext","description":"House number extension","type":"string","nullable":true},"valuationDate":{"type":"string","format":"date","title":"Valuationdate","description":"Valuation date","default":"2026-06-04"},"dateTransport":{"title":"Datetransport","description":"The acceptance date is the date on which you, as a buyer, become the owner of the house.","type":"string","format":"date","nullable":true}},"type":"object","required":["postalCode","houseNumber"],"title":"TransactionFinderInput"},"TransactionFinderResponse":{"properties":{"postalCode":{"type":"string","title":"Postalcode","description":"Postal code"},"houseNumber":{"type":"integer","title":"Housenumber","description":"House number"},"houseLetter":{"title":"Houseletter","description":"House letter","type":"string","nullable":true},"houseNumberExt":{"title":"Housenumberext","description":"House number extension","type":"string","nullable":true},"saleDate":{"title":"Saledate","description":"Sale date","type":"string","format":"date","nullable":true},"transportDate":{"type":"string","format":"date","title":"Transportdate","description":"Transport date"},"transactionDate":{"title":"Transactiondate","description":"Transaction date","type":"string","format":"date","nullable":true},"transactionPrice":{"type":"integer","title":"Transactionprice","description":"Transaction price"},"transactionPriceIndexed":{"type":"integer","title":"Transactionpriceindexed","description":"The price of the transaction, indexed to the valuation date."},"transactionPriceIndexedDateTransport":{"type":"integer","title":"Transactionpriceindexeddatetransport","description":"The price of the transaction, indexed to the transport date."},"transactionPriceIndexedDateSale":{"title":"Transactionpriceindexeddatesale","description":"The price of the transaction, indexed to the sale date.","type":"integer","nullable":true},"valuationDate":{"type":"string","format":"date","title":"Valuationdate","description":"Valuation date"}},"type":"object","required":["postalCode","houseNumber","saleDate","transportDate","transactionPrice","transactionPriceIndexed","transactionPriceIndexedDateTransport","transactionPriceIndexedDateSale","valuationDate"],"title":"TransactionFinderResponse"},"ErrorObject":{"properties":{"code":{"type":"integer","title":"Code"},"message":{"type":"string","title":"Message"},"errors":{"items":{"$ref":"#/components/schemas/ErrorDetail"},"type":"array","title":"Errors"}},"type":"object","required":["code","message","errors"],"title":"ErrorObject"},"ErrorDetail":{"properties":{"reason":{"type":"string","title":"Reason"},"message":{"type":"string","title":"Message"}},"type":"object","required":["reason","message"],"title":"ErrorDetail"}}},"paths":{"/mx-transaction-finder":{"get":{"description":"Returns a list of reference objects and their transaction prices.","operationId":"transactionFinder","parameters":[{"description":"Postal 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```

## The TransactionFinderResponse object

```json
{"openapi":"3.0.3","info":{"title":"Matrixian API","version":"1.0.0"},"components":{"schemas":{"TransactionFinderResponse":{"properties":{"postalCode":{"type":"string","title":"Postalcode","description":"Postal code"},"houseNumber":{"type":"integer","title":"Housenumber","description":"House number"},"houseLetter":{"title":"Houseletter","description":"House letter","type":"string","nullable":true},"houseNumberExt":{"title":"Housenumberext","description":"House number extension","type":"string","nullable":true},"saleDate":{"title":"Saledate","description":"Sale date","type":"string","format":"date","nullable":true},"transportDate":{"type":"string","format":"date","title":"Transportdate","description":"Transport date"},"transactionDate":{"title":"Transactiondate","description":"Transaction date","type":"string","format":"date","nullable":true},"transactionPrice":{"type":"integer","title":"Transactionprice","description":"Transaction price"},"transactionPriceIndexed":{"type":"integer","title":"Transactionpriceindexed","description":"The price of the transaction, indexed to the valuation date."},"transactionPriceIndexedDateTransport":{"type":"integer","title":"Transactionpriceindexeddatetransport","description":"The price of the transaction, indexed to the transport date."},"transactionPriceIndexedDateSale":{"title":"Transactionpriceindexeddatesale","description":"The price of the transaction, indexed to the sale date.","type":"integer","nullable":true},"valuationDate":{"type":"string","format":"date","title":"Valuationdate","description":"Valuation date"}},"type":"object","required":["postalCode","houseNumber","saleDate","transportDate","transactionPrice","transactionPriceIndexed","transactionPriceIndexedDateTransport","transactionPriceIndexedDateSale","valuationDate"],"title":"TransactionFinderResponse"}}}}
```


---

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```
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```

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