A word about scrimping and splurging. Everyone has their economic walls. I hit mine in expensive restaurants. I’m not mounting a moral high horse, because I don’t like eating rubbishy food either, and I really don’t like puritans who bore on about how morally bankrupt it is to spend more than 11p on anything.

I’m not saying a breakdown of labour and materials on a pair of £800 shoes would make literal sense. I’m not saying that I spend £800 on shoes. I’m just saying I get it. Just as I get why some people hanker after a Porsche. Look, even if you could get to the bottom of exactly how much it costs to produce a Kelly bag or a Lanvin dress, how much margin do you allow for Alber Elbaz’s mind? Or the fact that Grace Kelly was on the cover of Life magazine with a Kelly bag strategically held across her stomach to disguise her pregnancy. That’s social history. And maybe a bit of it is hype – just as no small part of Damien Hirst’s Golden Calf £10.3 million price tag is hype. But when you buy aspirationally, hype’s as much a part of the desire as the wrapping.

But, since now seems the moment for some sensible housekeeping, I’ve been sounding out women about what they will and won’t spend on. Teeth and hair seem to be non-negotiable. Always go for the best. Gyms, on the other hand, can be downgraded – it’s not how fancy they are but how hard you work when you’re there. Or run round the park. Bags are a moot point. The fever for a new one every season seems to have cooled. On the other hand, good quality never goes amiss. It’s quite handy if it’s also a fashion statement of some kind, bags being the most painless route to an up-to-the-minute look. So, at some point, the investment has to be made.

Shoes are another item where compromise is usually a bad idea. Even if you can find a cheap pair that look good, they’ll probably cripple you. Cashmere for the bargain price of £30 is also a waste of money (buy merino wool, it’s much more durable), ditto supermarket socks, which seem to fade after the first wash. As for cheap perfume? I’d almost prefer the whiff of (fresh) body odour. But, hey, a shower doesn’t cost much.

Here’s what you don’t have to spend designer prices on: jeans (Levi’s and Topshop’s B and Pippa versions are brilliant), T-shirts (£30 tops from Cos are great), coats (Gap’s grey pea coat, right, is an excellent bargain this autumn), jewellery (unless you’re planning on slipping out of the country in a hurry, fakes do a perfectly good job), petrol (the Times fashion team has discovered www.asos.com in a big way). Oh, and Abercrombie – it’s less than pounds for dollars in America. That’s just dumb economics.

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