A tragedy, in one graph:

Isn’t that awful? Isn’t that the saddest thing you’ve ever seen? A universally adored brand like Foxtons, losing a tenth of its value in an hour off the back of one bit of bad news? It couldn’t happen to a nicer firm. Perhaps it’s time for the inaugural CityMetric Christmas appeal.

Or we could not do that, on the grounds that banning letting agents fees is a thoroughly good thing, and estate agents are awful.

The move, which chancellor Philip Hammond is announcing in today’s Autumn Statement, will bar lettings agents in England and Wales from demanding tenants pay whatever fees they happen to feel like. (Those in Scotland are already barred from doing so.)

Lettings agents do have costs, of course: reference checks, credit checks, repairing the deliberate damage passers-by do to those minis in examples of what are basically hate crimes. In future, though, they’ll have to recoup them through landlords, rather than tenants.

The whiny, kneejerk, “pro-business” critique of this policy runs as follows. Any attempt to interfere in the operation of the free market will necessarily harm the weakest participants in that market. If letting agents pass their costs onto landlords, landlords will in turn pass them onto tenants. Ergo, the real victims of any attempt to stop lettings agents from torturing tenants any way they happen to feel like it will be tenants themselves.

This critique is, of course, a steaming pile of horseshit, spread about by the sort of people who have no shame about publicly announcing that they’ve not thought very hard about this and probably aren’t actually that clever. For one thing it’s obviously ridiculous. They’re banning parasitical middle men from demanding hundreds of pounds with menaces from renters whenever they have to do some photocopying – and you think that will actually harm renters? Are you high?

But no, let’s be fair to them and destroy their argument using actual logic. Yes, lettings agents do have costs. But there is no evidence that the fees they charge reflect those costs. Occasional CityMetric contributor Alex Parsons put together a report on this, available on the website lettingfees.co.uk. He found that the cost of new tenancy agreements varied from £48 to £450.

Administrative costs clearly don’t vary by a factor of 10: some of those letting agents are charging inflated fees, not because they have to, but because they can. By the time the fee is due, most tenants will have committed to their new home: the agents have them over a barrel. They’re price-gouging, and they should stop.

But there are legitimate costs, of course. Won’t these be passed onto tenants in higher rents? Very possibly – because, while the availability of property won’t change, the availability of money to pay for it will.

Even this is no bad thing, though, since at least they will be passed on consistently. At the moment it’s impossible for tenants to compare the real price of a new home, because are not shown in the advertised rent. Banning letting fees will introduce a much needed measure of transparency to the market.

There are other benefits to a ban. The added costs are likely to be more managable if paid as part of the rent, rather than in a single, upfront lump. It also means an end to unpredictable extra fees, when individual tenants leave houseshares or contracts otherwise need amending.

But if you’re still not convinced, there’s one more way you can tell that the real victims of this policy will be estate agents, rather than tenants. It’s this:

There is a reason that has happened: investors think this policy means that less money will now be going to Foxtons.

It’s a tragedy. A real tragedy, I tell you.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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