Online agents gaining media coverage because of their allegedly cheaper fees could actually cost sellers dearly.

The claim is from Cornish agent Chris Wood, who is calling on journalists and housing commentators to do their homework.

He says that 70% of vendors who put their homes on the market do not go on to sell, and they will have therefore wasted their money.

Wood, of PDQ Estates, said: “The hidden costs of putting your home up for sale with an online agent do not appear to have been calculated by many journalists or consumer champions, and have been conveniently left out of these agents ‘savings’ calculations in their advertising literature.

“Put simply, if online agents had every property currently up for sale on Rightmove (1.2m homes) and sold a typical percentage of that stock (average industry norm is circa 30% of stock) then the 70% of customers who didn’t go on to sell (all 840,000 of them) would have paid over £500,000,000 (half a billion pounds) to these firms for nothing.

“Not much of a saving for the vast majority of their customers, in my view.

“The traditional high-street agent, however, would have charged all those unsuccessful customers a cumulative total of around £0.00.”

Wood has based his figure of half a billion pounds assuming an upfront fee of £600.

He said: “Journalists and consumer champions, please do your sums before singing the virtues of these allegedly cheaper agents.”

His blog is here