From Monday, it will become illegal for price guides to be given at auction sales, and agents will not even be allowed to discuss prices.

The ban does not relate to the UK but to Queensland, Australia, where agents are reportedly up in arms.

The new Property Occupations Act could have had an even greater impact: the original Bill would have banned all price guides, so for example, online home hunters would not have been able to search for properties within a particular budget.

The ban is being introduced to prevent “price baiting” – attracting would-be purchasers by under-stating values. Agents who break the ban by giving price guides will face steep fines.

The Queensland government believes that under-quoting has been a serious problem. Reportedly, it is thought that agents routinely underquote auction guide prices by around 20%.

The size of the auction market in Queensland as a whole is unknown, but some agents have claimed that far too many properties are sold by auction.

In Brisbane, auctions account for almost 7% of all property sales. Agents themselves seem to play a far more proactive role in the auction process than in the UK.

John Mcgrath, CEO of Sydney based McGrath Estate Agents, says the ban is one of the most ludicrous steps in real estate that he has seen in years.

He said: ”This in my eyes is a 50-year step-back into the dark ages when agents held all the power and all the information.”

McGrath has since resigned from the Real Estate Institute of Queensland, which supported the proposal.

Another agent furious about it is Andrew Winter, who used to be an estate agent in Canary Wharf, London, and who successfully presented the Channel 4 Selling Houses series.

Winter, who has since emigrated to Australia where he now presents Selling Houses Australia, said: “It will become illegal for agents to sell a home by auction and list a price guide of any type.

“But that is not the real shocker here. Guess what –real estate agents, who are paid to sell/negotiate, will be banned from discussing prices, sellers’expectations, or even what a home sold for down the street.

“If they even mutter a hint they will be fined. The regulatory body is even sending out people to real estate agent offices to warn them. So no matter how keen you are to buy, no matter how much you beg, email or phone, agents risk their licence and fines.

“Have you ever come across anything else more stupid?”