Our interview begins when Charlie calls me in my London office at 6pm. He is away on business in America and the time zone difference means his working day has just begun. As we start to speak, I am welcomed by a strong, husky cockney accent that makes me feel right at home with the multi-millionaire who, in his fifties, was never going to forget his humble beginnings. When I ask him to describe his upbringing, he tells me that growing up on a council estate was a 'leave in your box situation' and that the only source of motivation was a local plumber. "He was my inspiration. He had loads of money, a nice motorbike, nice home, and he told me I'd earn loads and always be in work if I became a plumber like him. I didn't wanna be poor, and I was desperate to improve my life and not just go along with the flow, so I started bunking off school and helping him on his jobs."

Ditching education for the working world, Charlie tells me he left school at 15 with no qualifications ("I should have left at 14 because I knew I wanted to be a plumber so the other year was a waste of time.") Immediately, Charlie enrolled on a four year apprenticeship and soon became a self-employed, qualified plumber. Before long, his impeccable service and hard work built customer demand, quickly discovering he had more clients than he could service. By this point, Charlie started to recruit fellow plumbers and worked on a USP based on his own services at the initial stages of his business. "You can be a successful plumber if you conduct yourself in the right way but unfortunately most plumbers still don't act professionally. Back then, plumbers had this stigma of not wearing the right uniform, turning up late in a rusty old van and ripping off the customer. I wanted to change all of that, so I produced this book called 'The Pimlico Bible.' It had rules on work ethics, addressing the customer correctly and how to train others to become plumbers."

With a business concept in mind that would overturn an existing industry rapidly losing public confidence, Charlie set to work, renting the basement of an estate agents in Pimlico to begin formulating a plumbing service chain. Soon after the company successfully covered all aspects of the domestic services sector, including electrical wiring, heating and roofing to their offering. With a celebrity client base and his highest earning plumbers raking in £100,000 a year, Charlie says "Pimlico Plumbers has been built on hard work and quality service - the customers pay for a prestige service and I pay my plumbers accordingly." Not only do his employees fair well financially, but the company was also hailed as an equal opportunist, gaining publicity through hiring Britain's oldest worker, Buster Martin, who died last year aged 104. The plumbing firms press exposure didn't stop there, with Charlie telling me that he dedicates three days a week to promoting the company, working alongside PR guru Max Clifford, who Mullins declares "is very much like me - he has a basic background, he's straightforward and he doesn't take any shit." I then put forward the idea that in the same way Charlie leads the way in the plumbing industry, Max also prides himself in being the king pin of the PR game. "I think he's the best publicist in the world and yeah, we do have alot in common. He's very black and white and he say's it like it is."

As well as working the press circuit to put Pimlico Plumbers on the map, Charlie has used his new-found celebrity status for a positive cause, appearing on Channel 4's  The Secret Millionaire as well as being placed on the judging panel on the BBC's Young Plumber of The Year. However, perhaps his strongest work has been through his government initiative in support of apprenticeships, appearing on a recent documentary that highlighted the importance of hiring apprentices in the workplace, particularly during what is now being deemed a double-dip recession. "I spoke to George Osborne and told him my thoughts on unemployment in the UK. The simple solution is that companies need incentives to take on apprentices, because no business wants to fork out £15,000 a year to pay a  new worker. Instead, government should give benefit money to the employer to put towards a minimum wage to give to the apprentice. Instead of signing up for the dole, the unemployed can gain an apprenticeship using that money. I spoke to that David Cameron fella in Downing Street about this idea and he said its great but he doesn't know how to implement it. George was definitely more in favour of it."

His government influence doesn't stop there. When asked by Boris Johnson after the London riots how he would cut down crime, Charlie reiterated the same message. "Kids go out and commit crime because they don't have a job and they're bored. Give them a job, and you'll start saving money sorting out crime on the streets." Charlie has now implemented the idea himself with the Pimlico Apprenticeship Scheme, turning Job Seekers Allowance into a Job Achievers Incentive, declaring that if the same programme is used nationwide unemployment will be cut by 50%. Mullins also works closely with the Prince's Trust, providing mentorship and workshops for youths in the community. When I ask Charlie if more entrepreneurs could be helping the cause, he mentions another rather famous London business owner who publicises his use of apprentices. "I've had run-ins with Alan Sugar and I think he sends out the wrong message. Apprenticeships are nothing to do with his programme - he just has a bunch of half-wits running around trying to please the 'Lord.'

The difference between me and him is I was an apprentice myself and I want to show people what it's really like. With the Prince's Trust we do 'Pimlico Tours' and we get 20 youngsters, give them lunch, show them what the workplace is like and 99% that come and see what we do have never been to a workplace before and now all they want to do is get a job. We're working with 16-25 year olds now and we want to implement the programme in schools."

Whilst this interview has been my most honest, telling encounter with an entrepreneur yet, I wonder if Charlie's background is as simple as his wholehearted passion for plumbing without any mention of extra-curricular interests outside of a world of blue overalls and toolboxes. When I quiz Charlie as to whether he had any hobbies or interests outside of work, he mentions quite endearingly a love of amateur boxing between the ages of 15-21. "I loved boxing but for medical reasons I had to give it up. I was fighting for London against Wales and when I was knocked out I caught my head on the ring and they took my license. That was my passion and I still follow it - both of my sons box and one of them is an amateur boxing trainer so I'm still involved."

On the mention of his family, Charlie is only too happy to reap praise on his wife and children. "All of my family work with me, my wife, my grandchildren, my kids...my success is all because of my family and my favourite saying is that everyone that works for me is drinking from the same teacup." Not only is Charlie completely down to earth, he was very eager to credit his family before the interview came to a close, telling me that without them, Pimlico Plumbers would have never been possible.

So what does the future have in store for the company outside of Charlie's philanthropic efforts? "We have just set up in Marbella in Spain with a small operation - I plan to expand on that. We've been there for two or three years now and we're doing very well."

Charlie's interview appears in the latest issue of Entrepreneur Country Magazine.