Many self-builders will have architects working closely with them – but most of the ones on the series did not.

For these people, I acted as a kind of mentor, helping maximise the potential of buildings that might otherwise have been ordinary, or soulless.

At times, yes, I had to use the power of persuasion, and try very hard to change people’s minds – because diverging from what you know and think you already like can be pretty scary.

There’s a huge amount of trust, and a great responsibility to act wisely on this trust.

A criticism that might be levelled at an architect is that we just hoist our opinions on an unsuspecting client.

But we’re trained to solve other people’s problems by finding inventive and imaginative solutions. Ideas are our main currency – not just drawing up what someone has asked for.

I’d say that the episode which meant the most to me was episode two – Sumati is a great example of one of the self-builders in the series that rose to the challenge of the new.

Initially, she was so browbeaten by the dilapidation of her existing home that she was not aware that there was any alternative to replacing her house in the most rudimentary way possible and so she’d instructed an architect to draw up the most basic of plans.

The house that she had had designed lacked, as we pointed out, any joy.

By showing her that there were alternative solutions to planning her house layout and raising the ceiling to maximise the sense of space, showing her there were potential savings in going beyond the obvious choices for finishes, she has a house that fills her with delight.

There were many changes that Kieran Long and I would love to have suggested to all of the self-builders on the series, but most already had planning permission when we got involved with them, meaning that we were bound to work within their original consent.

There was an extraordinarily steep learning curve for most of the self-builders, not just in terms of design, but also in terms of construction.

They all had limited building experience yet they all had a sophisticated challenge – that of building an extremely low cost house.

Very ordinary houses in the UK typically cost around £1000 sq m – and a bespoke, one off house usually starts at around £1500 sq m, yet many of our self-builders were aiming for close to £500 sq m, which meant being ingenious on so many levels.

They were all pushing boundaries - very brave indeed!

My main piece of advice is to engage a really good architect early on, even if they don’t supervise the build.

They will be able to negotiate planning permission (all being well!), and should be able to work with a self-builder’s budget and knowledge, and design appropriately.

It is essential to budget. Rather than beginning with a pot of money and spending without a plan, do prepare a cost plan that allocates sums of money for each aspect of the build, and stick to it rigorously.

There’s something that we call ‘creeping enhancement’ - which is the tendency to keep embellishing or enhancing a project once it is underway.

Avoid creeping enhancement at all costs, otherwise you will shoot over budget.

Finally – building a house is a little like having a baby. It is incredibly painful and angst ridden at the time, but pretty soon you forget the pain of childbirth and enjoy your beautiful creation!

Good luck!

Piers Taylor is an architect and alongside Kieran Long presents The House That £100k Built.

The House That £100k Built continues on Wednesday, 2 October at 8pm on BBC Two and BBC Two HD. For further programme times please see the episode guide.

Comments made by writers on the BBC TV blog are their own opinions and not necessarily those of the BBC.

You either talk to Robin, the head of communications or his assistant Michele. There’s nobody else. But, amazingly, I found they were almost always at their desks and answering their phones.

In the age of email, when it’s often impossible to actually talk to someone, it was a refreshing change.

Direct communication is in Ryanair’s DNA. Chief executive Michael O’Leary, has an aversion to anything which interrupts what he calls “a culture of action” – including such new-fangled technology as voicemail.

I once called Howard Millar, the deputy chief executive and got this blunt message: “You have been forwarded to a voicemail system. The person you are calling does not subscribe to this service. Goodbye.”

In other words, try again later and waste your time not mine.

And although Ryanair staff do use email, they are strongly discouraged from sending emails instead of walking down the office and talking to the person they’re dealing with.

The founder of Ryanair’s biggest low cost rival in the UK, easyJet, shares O’Leary’s desire to keep things simple.

Sir Stelios Haji-Ioannou says he had the advantage of not knowing much about the airline business when he launched easyJet.

That’s why he didn’t take no for an answer when he asked his staff to sell the drinks and refreshments on board.

“It sounds trivial but when I went to the catering company and said I wanted to sell coffee on the aeroplane, they said we don’t have a way of selling coffee. Nobody has done it before... So I said, 'Let’s find a way of selling coffee.'"

Stelios and O’Leary were both larger than life characters, always ready with a soundbite and happy to play the role of underdog in relation to the established airlines.

The media lapped up the competition between these new pioneers of low cost travel and the established airlines.

Stelios stopped chairing easyJet more than 10 years ago, so we met in his London townhouse.

My colleague Erica Gornall and I were ushered into the front room, and told by Stelios’ head of communications where he liked to be filmed (in front of the marble fireplace).

In fact, he’s not keen on interviews these days, and it took us five months of gentle persuasion before we were allowed to bring our camera along.

Stelios now runs easyGroup, which is a collection of businesses spun off from the original easyJet idea. But easyJet is still the giant.

As its biggest shareholder with more than a billion pounds worth of equity, Stelios says, with a smile, he still keeps an eye on the business.

At easyJet headquarters in a converted hanger at Luton Airport, there’s still a palpable no frills culture.

Chief executive Carolyn MacCall shares a desk with her PA at the edge of acres of other staff, underneath live screens running tickers of the latest numbers of seats sold.

O’Leary does have his own office, or rather, he works in the conference room, from where he can survey his colleagues through a window. But he’s not grand.

There’s a shed behind the Ryanair office which sells pre-packed sandwiches and soft drinks.

I stopped there for a snack while we were filming, and the woman behind the counter told me that O’Leary was in most days to buy his lunch to take back to the office.

Stelios and O’Leary have a mutual respect. O’Leary told us that Stelios should be given credit for not living off the fortune he would have inherited from his shipping tycoon father.

And Stelios told us that O’Leary had done well to improve his financial position at Ryanair.

“I think Michael is undoubtedly a very clever man. It’s amazing how he managed to get the founder of Ryanair, the late Tony Ryan... to gift him such a big part of the company.”

He adds with a chuckle, “but timing is everything, and he was in the right place at the right time.”

It hasn’t always been like that between them. There was a legal dispute which O’Leary, characteristically, offered to settle with a race round Trafalgar Square - why waste the chance for some free publicity?

When Stelios said he might find himself at a disadvantage in such a contest, O’Leary refused to spare Stelios’ blushes and suggested he’d be happy to try sumo wrestling instead.

If most businessmen were as outspoken and colourful as Stelios and O’Leary, business journalism would be a much livelier, and easier, trade.

Charles Miller is the director and producer of Flights And Fights: Inside The Low Cost Airlines.

Flights And Fights: Inside The Low Cost Airlines is on at 9pm on Thursday, 20 June on BBC Two and BBC Two HD.

More on Flights And Fights: Inside The Low Cost Airlines
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Comments made by writers on the BBC TV blog are their own opinions and not necessarily those of the BBC.

When I met with Lord Bilimoria, I learnt that he started Cobra Beer in a recession. That's a huge boost to the confidence of any budding entrepreneurs out there, and drives home the point that now is as good a time as any to get your ideas off the ground.

As you might expect, all of the entrepreneurs that I met shared some common characteristics – they were extremely driven, willing to take a risk and passionate about their ideas.

Laura Tenison of JoJo Maman Bébé and Judy Naake of St Tropez self-tan both described how they felt that they weren't good enough for their parents and how this inspired their ambition.

I do think this can underpin an entrepreneur's hunger. Entrepreneurs are focused on doing and that means proving to themselves and others that they can be successful.

Many of us are motivated by self-doubt and on a mission to achieve our goals - while recognising that we are also our worst critics.

However, speaking to John Timpson of Timpson's, a close-knit, family run business demonstrated that family tensions are not always at the heart of an entrepreneur's drive.

At one stage or another, every one of the entrepreneurs had received help and advice from a mentor which allowed them to develop their commercial skills and play to their strengths. This cements my view that entrepreneurism can and should be taught.

Every entrepreneur had their own style and way of working. Laura said I was simplistic in looking only at the figures and not the emotional team spirit.

I say the first rule in business is to remember that cash is king. Without keeping on top of your finances you can easily lose money.

Lose too much and your team's spirit will soon drop when you have to make them redundant. That doesn't mean team spirit isn't vital - of course it is.

One thing entrepreneurs realise is that it's all about hiring the right management team to grow your organisation.

While team spirit is vitally important you can't lose sight of the financial management of your business. The two go hand in hand.

Ultimately every one of these entrepreneurs has seen huge success, which I think has been down to a combination of determination, vision, luck and sheer hard work.

That said, I'd like to make changes to all the companies I looked at in this series. Doesn't matter who owns them, there's always ways to make them better.

The entrepreneurs I spent time with could all give me some great pointers I'm sure, if they spent time with some of my businesses. Nothing is perfect in any firm.

Would I say there are there any flaws in the entrepreneurial spirit? Of course not!

Yes, you need to be driven and single-minded - but these are qualities that are crucial to success and no entrepreneur would get where they were without them. And of course, the rewards are worth it.

Peter Jones is an entrepreneur, a Dragon on Dragons' Den and the presenter of Peter Jones Meets...

Peter Jones Meets... begins on Sunday, 2 June at 6pm on BBC Two Scotland and 7pm in the rest of the UK on BBC Two and BBC Two HD. For further programme times please see the episode guide.

Comments made by writers on the BBC TV blog are their own opinions and not necessarily those of the BBC.