Does money make the world go around or the earth move? Is it power or sex? For Heather McGregor it’s all this and more. “Money is the last taboo. People would rather tell you intimate details of their sex life than talk about their bank,” she says. Breaking that taboo is the over-arching ambition of the woman best known as Mrs Moneypenny, author and aviatrix, financial expert and entrepreneur, whose latest book aims to make all women financially free of men. But as I went to meet her, I had more mundane reasons for reflecting on the seismic power of money matters.

As keynote speaker at The Gloss Magazine’s Look The Business event back in 2013, Mrs Moneypenny prescribed carrying an Anya Hindmarch Ebury bag (half briefcase, half handbag) with the Financial Times protruding. In tribute to her, I adopted the dress code. And found myself feeling such inordinate confidence, I began to worry. But I should have worried less about the ego trip and more about the wire trip – a loose airport cable. In a split second I hit the ground, face first. Which is how I turned up to meet the mythic Mrs Moneypenny, looking like a boxer.

I don’t know if that’s the reason she ruled out the tearoom at The Marylebone Hotel and headed decisively for the bar. But I do know that if you want the benefit of her wisdom, you don’t waste time arguing. It’s the critical distinction between a guru and a life coach, about which she’s emphatic. “A life coach spends time discussing options to allow for decision making. I am prescriptive. I tell people what to do.”

I came armed with questions from friends and colleagues. Who knew that mortgages and investments so exercised the minds of young women? Or that a pension was a cross-generational anxiety? She addressed each meticulously, but first there’s some celebrity spotting over soda and lime in the humming bar. A prominent magazine editor – “Shouldn’t she be at the international fashion collections? Hmm.” This social sharpness is hardly surprising in one whose business is identifying executives for communications organisations. But McGregor is equally sharp about her own life. “I spend more time talking money than I do having sex,” she announces. “After 27 years of marriage you don’t have a lot of sex.”

It would be a mistake to see this as a confessional moment – after all she took him to Chicago for Valentine’s Day – it’s just one of the dramatic metaphors she uses to illustrate the proportionality of money in our lives. Their three sons – whom she calls Cost Centres 1, 2 and 3 – are all held up to similar scrutiny in her work. A therapist might have a field day, but she has little time for it (expensive and uncertain return). The one time she attended, at a spa, the “therapy space” yielded a eureka moment: she needed to change her mortgage. “Everybody should, every few years.”

Her prescriptions come quick and fast. “Everybody should spend one hour a week on their money.” If that one hour is informed by her lists of tips from saving on utility bills (hang clothes up to dry) to getting ahead in your career (nothing wrong with a little flirting) it will be entertaining too. And get the pension fast: “Every euro spent before 40 is worth two after. Set up a standing order for €10 a week, because a pension is like sex, you can’t get it back if you let it slide.”

She recently invested in a shop in her village as part her pension fund. “Cost Centre 1 asked if he could turn it into a bar. I thought about all the education he’d got, but he was serious. He is now working hard and already has planning permission.” Though she has only just turned 50, she exudes the spirit of the “Mustn’t grumble” generation of World War II women. It’s the spirit that made their empire great and fittingly she was awarded a Commander of the British Empire honour last year for services to business and for her charity, which works to equip ethnic minority graduates for jobs in communications.

“In the early days the charity took all the profit. Had I kept that up I would have had no business. Now I have covenanted a fixed amount of money into it. I pay myself a salary, I pay a dividend and I have given away 20 per cent of my company to my staff.” She did this “because I wish someone had done that for me.” She pauses. “Because I want to change the world. My dream is that every child would have an education.”

Childhood is clearly where the fire under McGregor was lit. “I started life as the child of a single mum.” Her father, “an absolute shit,” abandoned them when she was two and died when she was 13. “For my own 40th birthday I decided to erect a headstone for him. I did not know what to say so I put the word “Entrepreneur.” It’s what I want on my own headstone. I intend to have little left to leave to the children – they’ve had a first class education. I do not want a headstone with “She was mortgage free.” No. “All that she gave” would be more apposite.

If she is a revolutionary, it is with a manifesto that success should be built on generosity. Including re-gifting. It colours her life and is reciprocal. “Shortly after Sarah Brown left Number 10, a package arrived with six lovely pieces of costume jewellery she had worn as the prime minister’s wife. “Will I come across as a terrible namedropper?” The law of attraction is sufficient explanation. Her friends, Jeanette Winterson, Anya Hindmarch, Miriam Gonzalez Durantez, Amanda Wakeley, are equally inspirational. Surely her glory is she has such friends.

As I walked down Oxford Street, head buzzing with ideas, I felt a rustling. A hand picking my Ebury bag. All it got was the FT! Method in the Moneypenny.

Illustration by Lauren O’Neill