When Chelsea Clinton is walked down the isle by her dad on Saturday, she'll do so at a mystery venue, in front of celebrity guests like Steven Spielberg, Barbra Streisand and Tony Blair ( lucky girl) . She will also do it for an estimated cost of £2 million.

And while the cost of her wedding to financier Marc Mezvinsky is unlikely to worry her dad, it needn't be so pricey. So how do you have a wedding with the trimmings, for less?

There is one word that can double the cost of everything you buy - 'wedding'. Utter the magic word and the cost of everything from the venue to the decorations suddenly becomes up to twice as expensive. It's something that brides have been convinced about for years, and an investigation by Which? has revealed it's completely true.

And while Crown Princess Victoria of Sweden isn't likely to be too fussed, after splashing the cash on her nuptials this week, the rest of us can be left seriously struggling. So just how bad are the wedding rip offs, and what can you do to stop them?

It seems that the days when the bride's parents would pay for the wedding are gone.

New research reveals that couples in Britain are now more likely than their parents to be footing the bill for their big day. And it takes them on average ten months to save up for the big day.

David Walliams and his supermodel wife Lara Stone were married at Claridges yesterday, after reportedly spending £80,000 on the event. It was a celeb-studded ceremony, with guests including everyone from Ronnie Corbett to Elton John, Denise Van Outen, Richard and Judy - and of course Matt Lucas.

There was no expense spared on everything from hiring furniture to the flowers (pictured). But £80,000 is an insane amount of money to blow on a party. So just how did they spend it? And can you get the look for less?

The average wedding guest spends a total of £380 in the run up to and during the day, according to new figures from Santander Cards.

As a nation, that means we pay an incredible £10.45 billion a year on stag and hen dos, wedding outfits, travel to and from the venue, accommodation and presents.

It's every girls dream - being bought a gorgeous bit of bling by the one you love. And films do nothing to help the poor guys out there who feel under pressure to buy the perfect rock - some girls really are obsessed.

Some of my friends have even started telling me what setting they'd like their diamond in, which cut and how many carats they want, in case their boyfriends ask me for advice when the time comes to pop the question. If that's got you quaking in your boot lads, don't worry - there's good news to follow. Small diamonds are in vogue.

Simon Cowell has spent a few years building up to his wedding, so he can be forgiven for going a little over the top. However, according to his mum, he may go to impressive lengths even for him - getting married four times to fiancee Mezhgan Hussainy.

His mum claimed they will have four weddings - one in Barbados, one in Hollywood, one in LA and one in Brighton.

It's slightly perplexing - why would anyone need so many weddings?

There's a chance the plans outlined by Simon's 84 year old mum may be a deliberate or accidental smoke screen. But if he is planning four weddings, will this push him into the realms of the world's most expensive wedding?

He has some tough competition to beat.

Diamonds are a girl's best friend.... or are they? Your engagement could cost you dear this year as double digit growth in rough diamond prices threatens to send jewellery prices sky high.

Since March 2009, rough diamond prices have risen by 55-60%. This is down to a lack of bank lending and many suppliers cutting production by up to 50% in response to the credit crunch.

Polished diamond prices are obviously dependent on the cost of rough ones and it won't be long before the price of polished diamonds shoots up, warns online retail jeweller Diamond Manufacturers. So it's really important to shop around if you're buying an engagement ring this year and you may want to do it sooner rather than later.

Have Charlotte Church and Gavin Henson restored your faith in romance? After a run of high profile break ups, this couple has endured a few years with tiny children - surely the hardest part of any relationship - and come out the other side still wanting to wed. Is this enough to make you consider a proposal?

Or is the massive cost and the potential for an expensive divorce a few years down the line putting you off?

If so, perhaps the lowdown on the tax breaks in marriage may help.

They promised themselves they would wait until their 30s before tying the knot, but after five years and two kids together, at the tender ages of 24 and 28, Wales' power couple Gavin Henson and Charlotte Church are engaged.

The couple have kept things under wraps since February, but came clean in an OK exclusive, and have started the wedding planning frenzy.

But even before they get anywhere near the church, the couple have already invested an impressive sum, because Gavin's proposal didn't come cheap.

He bought a huge engagement ring in Dubai, then on the day of the proposal he flew Charlotte by helicopter to Truro for a slap up meal and a walk along the beach, where he dropped to one knee and kicked everything off.

He apparently got her drunk the night before because he reckons she's more sentimental when hungover, and therefore more likely to say yes, which was a nice touch.

None of this came cheap, and alarmingly it's part of a trend towards spending ever-larger amounts on a proposal.