Outside Edge: Sabine Durrant on the private collection of Yvonne Vinall

YVONNE VINALL was 40 when she first took her clothes off for money. Her husband didn't mind, but some of the people she knew looked at her oddly. 'They'd say, 'I mean, God, Yvonne, doesn't it bother you?' ' One of her friends wanted to do it, too, but her husband wouldn't have it. 'I'm not letting you do that,' he said, 'not what Yvonne does.'

Yvonne didn't blink an eyelid. She'd go up to London in the train - first class, all paid for - and come back a richer woman. Sometimes they'd buy her tea afterwards. Once, a man took her to Italy and kept her in his house for a whole month. Yvonne just smiled, peeled off her dress and wallowed in the light: 'Beautiful, the colours . . . so sensuous.' She charged pounds 1.56 an hour back then, but it's more than that these days - much more. Professionals like Yvonne Vinall can name their own price.

She's been doing it for 21 years now, which makes her 61, but the customers keep coming. Good artists' models don't grow on trees. In her time, Yvonne Vinall has sat for the Royal Academy, the Royal College of Art, the Slade, for Westminster, Harrow and Eton, not to mention for the Adult Education Centre in Monson Road, Tunbridge Wells. 'It's my loyalty,' she says. 'My punctuality. My sense of humour. And perhaps the texture of my skin. I'm what you'd call firm Renoir-ish. I can also hold very difficult positions; for really quite long periods of time. One man had me on tiptoes, hanging on to a trapeze bar from the ceiling - he took ages with that; about a year off and on. It almost killed me. Oh, and another thing, evidently I never move.'

Some of her artists, so impressed by her stillness, have told her she exudes a kind of beatific calm. This she puts down to her inner peace. 'I've always been able to just sit, doing nothing. I drift off, you know when you're coming round from anaesthetic, you hear voices but you're miles away? Usually I hardly think of anything at all, but if I do it's good thoughts, beautiful thoughts . . .'

Perhaps even acquisitive thoughts? Over the years, the beatifically calm Yvonne has proved herself admirably adept at sidling over to the artist and slipping away with a brown paper roll under her arm. 'I think I bought one once,' she says airily, 'but mainly they give them to me free.'

The front room of her council maisonette in Tunbridge Wells is lined with more than 50 oils, watercolours, charcoals and sculptures with one thing in common: they're all of her. Predominant are good, striking pictures by students and unknown artists (including two busts, and one hand in Portland stone), but there are some hidden gems: three sketches by Edward Ardizzone ('I can still smell his snuff'); a woodcut by Eduardo Paolozzi ('Oh, what a lovely man]'), two Philip Sutton prints (one of his cat, and one 'Yellow Nude' - 'I don't think that one's actually me'); and a bronze resin statue by John Rivera representing his larger work On the Town (Yvonne is the mother figure) which stands on the Thames at Battersea.

Yvonne wouldn't dream of parting with any of them. She says her front room is her 'visual diary'. Others might call it a canny collection.