A challenge: you’re a Tory chancellor and you need to get re-elected but your future voters are unhappily stuck in the rented sector.

How can you move them into true-blue homeownership without losing the votes of your core older home-owning, countryside-loving, business-running constituents?

You pay a ransom, with taxpayers’ money of course, giving them an interest-free loan towards buying a new or existing home with just a 5% deposit.

Here’s the effect on the average price paid for a property in London by first-time buyers (the blue line), indexed to the growth in rents in London (the yellow and green lines) since the start of 2012.

At what point do first-time buyers [whether opting for Help to Buy or not] twig that they’re being sucked into taking on huge debt at stupid prices and start to shy away? The interest-free period only lasts five years.

At what point do taxpayers start to worry that they take the losses on the Help to Buy loans?

And at what point do we check who got the ransom money?