Up to a quarter of homes of a £1 million or more are thought to be purchased 'off-market' to avoid paying the 5% Stamp Duty.
Holding UK properties through offshore companies also has potential for avoiding Capital Gains Tax.
The Institute of Fiscal Studies (IFS) has suggested scrapping Stamp Duty and revising Council Tax. A house worth £320,000 in 1991 currently pays the same Council Tax as a house worth £30million.
Under the suggested new IFS system, Council Tax would be around 0.6% of current values.
This would mean that most people would not face any rise in Council Tax under the new system.