{
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  "postcodes": [
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  "latitude": 51.52173188700195,
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  "location_precision": "postcode_centroid",
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      "county": "GREATER LONDON",
      "ppd_category_type": "A",
      "last_seen_at": "2026-07-09T18:56:26.350736+00:00",
      "address_path": "w1u/chiltern-street/portman-mansions/flat-4n",
      "property_url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n"
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      "county": "GREATER LONDON",
      "ppd_category_type": "A",
      "last_seen_at": "2026-07-09T18:56:26.350736+00:00",
      "address_path": "w1u/chiltern-street/portman-mansions/flat-4n",
      "property_url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n"
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    {
      "url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n/ddb4b40a-d2f3-4602-851e-9276ea360e50",
      "transaction_id": "DDB4B40A-D2F3-4602-851E-9276EA360E50",
      "price": 647000,
      "date_of_transfer": "2009-05-29",
      "postcode": "W1U 6NS",
      "property_type": "F",
      "property_type_display": "Flat/maisonette",
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      "duration": "L",
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      "paon": "PORTMAN MANSIONS",
      "saon": "FLAT 4N",
      "street": "CHILTERN STREET",
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      "town_city": "LONDON",
      "district": "CITY OF WESTMINSTER",
      "county": "GREATER LONDON",
      "ppd_category_type": "A",
      "last_seen_at": "2026-07-09T18:56:26.350736+00:00",
      "address_path": "w1u/chiltern-street/portman-mansions/flat-4n",
      "property_url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n"
    },
    {
      "url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n/0b315c85-b3a3-4d0d-8c6b-91d86dcd886c",
      "transaction_id": "0B315C85-B3A3-4D0D-8C6B-91D86DCD886C",
      "price": 197000,
      "date_of_transfer": "1997-02-24",
      "postcode": "W1U 6NS",
      "property_type": "F",
      "property_type_display": "Flat/maisonette",
      "new_build": false,
      "duration": "L",
      "duration_display": "Leasehold",
      "paon": "PORTMAN MANSIONS",
      "saon": "FLAT 4N",
      "street": "CHILTERN STREET",
      "locality": "LONDON",
      "town_city": "LONDON",
      "district": "CITY OF WESTMINSTER",
      "county": "GREATER LONDON",
      "ppd_category_type": "A",
      "last_seen_at": "2026-07-09T18:56:26.350736+00:00",
      "address_path": "w1u/chiltern-street/portman-mansions/flat-4n",
      "property_url": "https://openproperties.uk/w1u/chiltern-street/portman-mansions/flat-4n"
    }
  ],
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains HM Land Registry data © Crown copyright and database right. This data is licensed under the Open Government Licence v3.0. Contains OS data © Crown copyright and database right. Postcode locations are Code-Point Open centroids: they locate the postcode, not an individual building.",
  "provenance": [
    {
      "source": "HM Land Registry Price Paid Data",
      "source_url": "https://www.gov.uk/government/statistical-data-sets/price-paid-data-downloads",
      "retrieved_at": "2026-07-09T18:56:26.350736+00:00"
    },
    {
      "source": "OS Code-Point Open",
      "source_url": "https://osdatahub.os.uk/downloads/open/CodePointOpen",
      "retrieved_at": null
    }
  ]
}