The current API version is '1.21'
Please see the change log below. Requests to older, depricated versions of the API will fail with an error message advising you to upgrade.
version 1.21 - 5 April 2011
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-- the search_listings service has been retired for Australia (metadata service remains)
version 1.20 - 25 Jan 2011
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-- possibly return the field 'price_coldrent'. Mainly used in Germany
version 1.19 - 29th Dec 2010
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-- new listing field 'location_accuracy' which gives an indication of
how accurate the latitude and longitude provided are. Number
returned is between 1 and 10.
version 1.18 - 28th Sep 2010
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-- new response fields 'application_status_code' and
'application_status_text' to indicate status of response
version 1.17 extended - 13 Sep 2010
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-- added ability to search by a list of listing GUIDs
version 1.17 extended - 13 Mar 2010
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-- keyword list includes local translations
-- updated_in_days_formatted (e.g. "one week ago") is now translated
version 1.17 - 2 Dec 2009
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-- new result fields: price_high, price_low. for ranged prices
-- new result field: auction_date. for listings with a price_type "auction"
-- new result fields: land_size, land_size_unit
version 1.16 - 21 Sept 2009
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-- support for bathroom_max, bathroom_min as filters
-- support for room_max and room_min and note of explanation in docs
version 1.15 - 10 Sept 2009
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-- we now return new parameters "img_width", "img_height" and "img_url".
-- also, if defined, "commission" and "construction_year".
version 1.14 - 14 Jul 2008
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-- added new parameters "guid" and "page".
version 1.13 extended - 3 Jul 2008
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-- added field "long_title" for each location.
version 1.13 extended - 7 Feb 2008
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-- added field "updated_in_days" for each listing.
version 1.13 - 22 Nov 2007:
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-- added ability to sort by "random"
-- added the "has_photo" parameter to only request listings
with photos
version 1.12 - 29 Oct 2007
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-- added the "metadata" function for retrieving metadata.
-- deprecated all API versions below 1.11.
-- added "attribution" and "thanks" fields.
version 1.11
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-- added ability to sort by "newest" and "oldest".
version 1.10
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-- added support for "radius" parameter.
version 1.09
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-- added "bathroom_number" method.
-- added "callback" param for JSON callbacks
version 1.08
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-- added "keywords" method.
version 1.07
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-- added support for "size_min" and "size_max" parameters for
nestoria.es.
-- added spanish keywords
version 1.06
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-- added support for "keywords" parameter.
-- added support for "keywords_exclude" parameter.
version 1.05
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-- added the "sort" parameter.
version 1.04
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-- fixed "centre_point" bug
-- added "share" as new listing_type
-- "pretty=0" now behaves as expected
version 1.03
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-- minor bug fixes to deal with default values for some parameters.
version 1.02
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-- listings now return "keywords" which is a comma separated list of
'nice-named' attributes of the property
version 1.01
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-- "version" no longer required, will default to current version if
not supplied
-- malformed requests (for example missing required parameters)
return XML, rather than HTTP 500 error as previously
-- we now return a "datasource_name" for each listing. The value is
the nice name of the site we link to. In some cases this might be
a property portal like "HotProperty" or "Fish4". In some cases it
will be the same value as "lister_name"
-- by default json results are no longer "pretty printed". Pretty
printing can be turned on by setting "pretty=1" in the request URI