The high school dropout who banked £80m

Mr Dolan sold his first business in a £100m deal

Not many people can trace their success - and multi-millionaire status - to an advert they placed in a local paper. But for Simon Dolan, a £10 ad promoting his accountancy services turned his life around.

Then aged 22, Mr Dolan had been on the dole for 15 months after he lost both his driving licence and his job through drink driving, resulting in spiralling debt and anxiety over his mortgage repayments.

But the ad worked. "A client phoned three weeks later and I did her accounts for her and that meant I could place another ad, which got another client."

After working as an accountant from his kitchen table for five years, in 1997 he opened the first branch of SJD Accountancy in Berkhamsted, 26 miles north-west of London. The firm grew rapidly and became a market leader in the contractor accountancy sector.

Mr Dolan has gone on to launch a chartered airline, among other business ventures

'Bigger and bigger'

With strong profits, private equity firms started circling. In 2014, with 14,500 clients on its books and a turnover of about £20m, Mr Dolan sold the company to Sovereign Capital as part of a £100m deal.

As SJD's outright owner, Mr Dolan says he banked £81m - although he is quick to point out his success happened gradually.

"We used cash flow to open other branches," says Mr Dolan, 49, who is from Chelmsford in Essex. "We never bought anybody, all the growth was organic. It was a nice business with no capital costs - short of computers and people."

He says growth came from always wanting to make more than the previous month.

"I made £800 the first month then after I wanted to do £1,000, so if you keep doing that over the years of course it gets bigger and bigger."

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However, the success of the firm also presented challenges: under his ownership a handful of staff tried to swindle money out of SJD, stealing sums ranging from £10,000 to £60,000.

"No one ever got away with it," Mr Dolan says. "It was hard but I know it wasn't personal. We employed 200-plus people at any one time and statistically someone is going to steal."

Wayward youth

Mr Dolan's success is perhaps even more unusual given he was expelled from school at 16, for, as he describes it, "always asking awkward questions".

The entrepreneur now describes the English education system as "pointless and impractical" and has criticised the "incessant" way young people are pushed towards university as a way to get good jobs.

"For me, I always have to see the practical purpose in something and if that doesn't make any sense to me then there's no incentive."

It was the activities he did outside school that ignited his passion for business. Aged 10, he had a paper round, and at 13 he sold scratch cards at school.

Mr Dolan celebrates his car winning its class in the 2014 Le Mans race, and coming fifth overall

He says he was always fascinated with numbers.

"At primary school I was good at maths, the money thing kind of flowed from there."

Racing driver

It's driven Mr Dolan to make some surprising - and colourful - investments. The serial entrepreneur started his own motor sport racing team, Jota Sport, in 2008 after his wife bought him a track day as a birthday present. Jota Sport was born out of an existing racing outfit called Team Jota.

It led to Mr Dolan, along with two other teammates, coming fifth in the 24-hour French sports car race Le Mans in 2014. The venture is also doing well financially, making about £8m in sales last year with pre-tax profits of around £500,000

Mr Dolan also owns Jota Aviation, a chartered airline based at Southend Airport, although his most recent business venture is perhaps less adventurous.

Last September he returned to the UK accountancy sector with Dolan Accountancy, a group he runs with some old colleagues. The model is "entirely the same" as his last accountancy business, he says, with added benefit that he now knows the industry "so well".

Will the new firm grow as fast as SJD? Certainly the UK accountancy sector is expanding, with the top 100 practices making fee income of £14.2bn in 2017 - up from £13.1bn in 2016, according to trade publication Accountancy Age.

Simon Dolan's racing team - Jota Sport - won its class in the 2014 Le Mans race

Challenging market

However, editor Emma Smith says the market faces some big challenges and Mr Dolan will have to be nimble.

"New regulations and increased compliance obligations are two key headaches for the accountancy industry. But perhaps the biggest challenge is technology.

"It is transforming the accountancy sector, shifting the role of accountant from one of compliance and numbers to that of strategic and trusted adviser to businesses."

While she says some accountancy practices have embraced the shift, "other firms are struggling with this".

Despite his success, Mr Dolan admits many of his business ideas failed to get off the ground - including launching a modelling company.

"It was a very small investment," he says, "but when I look back it was never going to make any money."

He says a perfume launch was his biggest failure. "It was always going to be a long shot but if you can get it right it can pay off very well, but I'm disappointed as I didn't pay enough attention to it."

The UK accountancy market is growing but faces challenges

Move to Monaco

In 2013, Mr Dolan left the UK for Monaco, a tax haven, where he still lives with his wife and two sons, aged 13 and 16.

"Our house was broken into and it was nasty. I have a young family and I didn't want to live in a place where I don't feel safe.

"So I started researching and found Monaco is one of the safest places to live. It was nothing to do with tax but it's a nice by-product."

As a multi-millionaire, does he ever feel tempted to quit his businesses and live a life of luxury?

"I did do that for about six months or so. But I love business, whatever form it takes, and I started ramping it up again.

"It's like being a footballer - they love kicking a ball around and they don't ever want to stop. If there's something you love, you don't want to stop."