Recuperation in Switzerland was followed by jobs — in television, the wine trade and selling printer cartridges — and some travelling: “I was hugely irresponsible,” she says. In her late twenties she begged and cajoled her way on to a postgraduate fine arts course.

After her diploma, in 1994, she joined the Malcolm Innes Gallery, in London, becoming a director before a short-lived marriage took her to Hong Kong for a year. On her return she set up on her own: “The Malcolm Innes gallery specialised in Scottish and sporting art. Yet despite the fact that it had dead stags on the walls, people would walk in and ask about having their portraits painted. I saw a hole in the market for a gallery to specialise in contemporary commissions, particularly portraiture.

“I started in the living room of my brother’s home in London. After two years I moved to an office above the Circle Line. When we were talking to clients on the phone, I would pray that a train wouldn’t go past.

“Once, we had a call from someone we thought was coming from Dorchester. We were astonished, when he turned up in a stretch limo soon after, to discover that he was a famous pop star who had taken a whole floor at the Dorchester.”

She won’t, alas, say who he was, but admits that clients include celebrities and members of the Royal Family.

Today, in her Fine Art Commissions gallery, now in Walton Street, Central London, portraits on display show how popular this art form now is, freed from its long associations with aristocrats and vanity. Sara also co-owns the Amdean Gallery in Cork Street, Central London, for artists and art dealers wishing to hire gallery space, and this is managed by Sara’s PA, Kate Sadler. “I go there once or twice a week and make sure that the gallery is set out how it’s wanted,” she says.

Kate, 25, has a unique perk — she is to have her portrait painted by an artist of her choice and the picture will hang in the gallery. She did a two-month course in Italian Renaissance art in Florence, before studying history of art at Bristol University. So could she have been an artist herself? “I know my shortcomings,” she smiles.

Kate is as passionate about art as Sara. With just the two of them at the gallery, did Sara recruit someone in her own image? She ponders the point: “I can’t stand a bad atmosphere and it is vital that we get on — which we do, very well. I made a conscious decision to choose a strong character. When clients come in and I am on the phone, I have no hesitation in letting Kate deal with them. She handles problems and when I am not here, she is me.”

ROSALIND RENSHAW

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