As a journalist I'm agnostic but I must say they - online agents - have a frankly odd fascination with cost.
Instead of emphasising flexibility, simplicity and modernity, they invariably drop the debate to one of price. Do they not know that 'cheap' does not equal 'good'?
Their emphasis on costs appears to me to be mistaken on two fronts.
Firstly, they risk creating the scepticism that has built up towards budget airlines.
Book a Flybe or Ryanair seat online and the headline price is indeed bargain basement. But add what the airlines call extras but the rest of us call necessities - luggage, advance booking, priority boarding and that little essential called eating - and you find the price is....well, not quite that of British Airways, but still not as cheap as the advertising led you to believe.
Some online agents risk the same with the extras they charge for - what many seasoned house sellers would regard as essentials such as a professional valuation, for sale boards, an infrastructure to arrange and accompany viewings, and so on.
The combined cost will not be two per cent of sale price, but may still leave a nasty taste in the seller's mouth when the amazing headline figure that attracted them has been multiplied many times over.
Secondly, online agents miss the point by saying that traditional agents are actually expensive to begin with. My research for Estate Agent Today shows that in comparison to many other countries, Britain's estate agents charge relatively little.
That may not seem the case when a seller says goodbye to £10,000 after selling their home for half a million, but in relative terms sellers already get a bargain with the agent. It's the stamp duty and other costs where the bill appears less justifiable.
Onliners could, instead, emphasise that in return for the two per cent commission, a seller still runs a risk of getting poor service from the small number of less-good traditional agents. There are fewer of these now than ever before in my experience, but we all know of high street agents ones who rarely accompany viewings, use under-prepared weekend staff or put only cursory details on the major portals.
That sort of performance is fair game for criticism. But criticise their cost? No, that's not really the point.
Surely onliners' USP is that they offer flexibility for buyers to register without schlepping into an office on a weekday when, in any case, most purchasers are at work?
And couldn't an online agency surprise us by saying it will use only highly trained staff - perhaps better than those you sometimes encounter at old-school agencies?
In other words, what about putting the emphasis on quality, not cost, in a business which is already good value when compared to, say, the legal profession?
This is what happens in the US where realtors in some areas have - for years now - operated without physical branches, instead using home offices and their cars.
They do this not to score points off the traditional agents but to emphasise the speed and efficiency of their offer - to give a choice to would-be vendors.
In fairness, a few of Britain's new online agents appear to be taking this higher road.
I was struck in a recent interview at how easyProperty's CEO, Robert Ellice, very sensibly said there was a lot going for the traditional estate agency business model.
He recognised that online agency was not going to handle all sales in the future and acknowledged that 'cheap' didn't necessarily mean 'good'. But he did say, rightly, that many people want to register their interest in buying or selling outside the hours of 9am to 5pm on weekdays.
If other onliners took a similarly enlightened view, the debate would be lifted and everyone could spend less time in their trenches. And instead, spend more time selling homes...
(This blog originally appeared in the Industry Views section of Estate Agent Today - an online daily newsletter for the agency industry)
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