The body representing auctioneers and valuers has described proposals by the Government to introduce a value-based property tax as "crazy".
The Institute of Professional Auctioneers and Valuers also questioned how such a tax would be implemented, how often valuations would take place and how these would be paid for.
In its latest report to the EU/IMF Troika, the Government says details of the design of the tax and its collection will be included in draft legislation to be published later this year around the time of the Budget.
It also describes the tax as a stable revenue resource.
Former Dublin lord mayor Andrew Montague said he is disappointed that the Government is planning to base the tax on the value of a property.
The Labour Councillor said such a move would be unfair to people who lived in cities and would encourage more people to move away from larger urban areas, resulting in more commuting, high fuel bills and adverse effects on the environment.
Mr Montague said a site tax would be a fairer and better way of introducing a tax on property.