27/08/2014 10:32 BST | Updated 26/10/2014 05:59 GMT

Don't Forget the Toilet Roll Holder

Do you know the five most terrifying words in the English language?

For the record, they're not "Your tax return is overdue'', or "Mum, I'm marrying a Moonie" or even ''Does anyone here know CPR?"

They are, of course, "Let's get the builders in".

Yet every year thousands of us employ these so called 'experts' to help our fantasies become a reality. Naturally, nothing's a problem at the beginning.

You show them a picture of Versailles and tell them that your upper limit is five grand. After a sharp intake of breath and a quick few (mis)calculations on their notepad, they inform you that this should be easily doable. (This is a bit like going into a branch of Mr. Toppers - around £10 for a haircut - showing the stylist a shot of Kate Bosworth and coming out with a number 1 more suited to Bruce Willis).

You then ask them how long it will take, only to be informed that a month shouldn't be out of the question. Now everyone knows that Rome wasn't built in a day, but a recreation of France's most celebrated chateau in just four short weeks? Probably not.

The truth is that for any work wanted you can unquestionably double the amount of time and while you're at it, double the budget as well.

It's a little known fact that if the builder's original quote had have been adhered to, the Great Pyramid at Giza would have been finished a decade earlier - around 2550 BC - and cost half of the £17 billion (in today's money) that it eventually ended up coming in at.

While the Taj Mahal (not the curry house at 12-14 Highfield Street, Leicester) would have been finished in 1645 instead of 1652 and cost 19 million Rupees. A pretty penny back then, I can tell you. Needless to say the cash saved would have bought a lot of Chicken Jalfezi and poppadoms.

Finally, our beloved St Paul's cathedral would almost certainly have been finished circa 1700, not 11 years later, and cost nowhere near its final total of £1,095,556. £143 million, if you're trying to work out the 2014 equivalent.

Before you select the builder, you should get at least three competitive quotes. You should also ask for references from past jobs. And demand to see examples of their latest work. If the most recent thing they built was an air raid shelter in 1938, you're best going with the other ones, despite them being a tad more expensive.

Once you're happy, or as happy as you can be, with your choice, you want to be confident that any contract is as tight as the space under your stairs. Heavens above, who was the contractor who said that there was plenty of room for a swimming pool, sauna and gymnasium?

Firstly, agree a price and make sure it's in writing with no possibility of them being able to deviate from it. In the event of natural disasters such as tornadoes, earthquakes, hurricanes or, worse still, repeated visits from Sarah Beeny, there should be some leeway.

Secondly, ensure that the payments are staged. Three are normally enough - 50% to begin with, 25% when half the work has been completed and the final 25% at the end of the job. But only when both parties have gone round with a snagging list and signed off on every last skirting board, cornice and light fitting. There's not much point in having the switches positioned 7 feet up if you're only 4ft 11".

Thirdly, include everything you want doing. It's no use waiting till the end of the job to say: "Where's the indoor shark tank (the one you may now want to throw them into) we verbally agreed on in July?"

Fourthly, stipulate that all works come with a minimum guarantee period. A little longer than a fortnight would be good.

Fifthly, clearly state a date by which the whole job should be completed. Then add a penalty clause for every week they go over.

Signed and sealed, the walls can at last start to be knocked down. "Oh dear God, not that one. It's load bearing". You can then concentrate on the fun bits of renovating. These include choosing new furniture, curtains, rugs, the kitchen appliances, the fixtures and, most importantly, the bathroom fittings.

Eventually, the heartache, unbelievable stress and petty squabbles will be over and you'll be left with a home that is quite simply beyond your wildest dreams with Elle Deco clamouring to photograph it. Either that, or you'll be left with a home that is quite simply beyond your most horrendous nightmares.

Frankly, you'd have been better off doing it yourself. That horrendous, eh?

Still, at least they fitted that rather fabulous Philippe Starck toilet roll holder you always wanted. It's just a shame they forgot about the toilet.