Hello
1) What is equivalent for US expresion «real estate» ( the business of
selling houses or land for building) in  everyday British and
Australian English.
According to «Oxford Advanced Learner's Dictionary» (international
edition), British «estate» is not the same as US «real estate», but
British «estate agent» is the same as US «real estate agent» and
British «real estate», «realty» and «real property» are normally
restricted to specialized use in law.

2) What is most common:
Sydney real estate
Sydney realty
Sydney real property
Sydney property
London real estate
London realty
London real property
London property
Regards
Nik
Any researcher from Australia or UK?

Gidday Nik,

I live in Australia, and also lived in the UK for 5 years, so I can
give you my impression, and then let Google verify it.

In Australia and the UK you won't hear the words realtor or realty
very often.

Australians (and New Zealanders) use:

Real estate
Real estate agent
Property

In the UK they use:

Estate
Estate agent
Property


Google search results
---------------------
Google is great for comparing the popularity of words and phrases.
Especially when you can search by country:

site:au "sydney real estate" 3170 results
site:au "sydney property"    2150
site:au "sydney realty"        45
site:au "sydney estate"        33
site:au "Sydney real property"  0

site:au "real estate agent"  13700
site:au "estate agent"       16200 (would include 13700 x real estate
agent)
site:au "realtor"             1740

site:uk "london property"    30600
site:uk "london estate"      18500
site:uk "london real estate"   911
site:uk "london real property"  70
site:uk "london realty"          2

site:uk "estate agent"      821000
site:uk "realtor"            18900
site:uk "real estate agent"   5800


Estate in the UK
----------------
The dictionary is right and wrong. In terms of selling property, the
English call them "estate agents". But estate on its own can have
these meanings:

 - A landed property, usually of considerable size. 
 - The whole of one's possessions, especially all the property and
debts left by one at death.
-  A housing development. 
http://dictionary.reference.com/search?q=estate&r=67

Each of which is a more common meaning (in my experience) than "real
estate".


Best wishes,
robertskelton-ga

For the UK, Estate is not a commonly used word in terms of the real
estate market. Words like Housing, Property or Residential are
commonly used. Commercial could be used for Offices.