The price was more than double what was forecast when London was named host seven years ago, never mind the government mantra that the Games were "delivered on time and under budget".
Prime Minister David Cameron, desperate to revive a recession-hit economy, has made London 2012 a centrepiece of his commercial diplomacy to sell UK Plc to visiting business chiefs.
The government says the Games will deliver economic benefits of 13 billion pounds in coming years - meaning they will more than pay for themselves - and brushes aside scepticism about the long-term effects of hosting major sporting events.
Yet away from the Games, the news has been bleak.
The central bank has warned the economy will not grow this year, the governing coalition partners are at loggerheads and Standard Chartered has become the latest London bank caught up in scandal.
Economists say the Games should help Britain's economy to return to growth fleetingly in the three months to end-September. Sales of tickets and T-shirts and spending by Games organisers will provide a short-term boost likely to fade fast.
After that, it becomes harder to distinguish the Olympic effect from what is happening in the broader economy.
"We're all having a great time but, similar to most parties, there's going to be a hangover," said Georgios Kavetsos of the London School of Economics.
"Mega events, such as the Olympics, do not significantly increase tangible outcomes such as economic growth, tourism, employment or wages," he added.
However, he said London might have a positive impact on British society.
"There is limited evidence on whether they might have intangible benefits, such as happiness and the promotion of healthy living."
The Games have certainly been a public relations boon for capital and country, helping to repair the damage done by images of youths burning and looting in English cities a year ago.
"London has looked very professional and slick on the world stage," said Sara Parker, London director for the CBI business lobby group.
"What the last two weeks have done is to show the diversity of what British business can do."
Britain went through a crisis of confidence just before the Games began, fearing that transport and security problems could make it a laughing stock on a global stage.
Those concerns have proved unfounded. The 70,000 Olympic volunteers ensured all went smoothly and venues in the centre of London illustrated the city's ancient and modern appeal.
"I was expecting things to be well organised but the warmth of the people has surprised me," said Manuel Parga, chief financial officer for the Madrid team bidding to host the Olympics in 2020.
"I lived in Paris for five years and used to think it was the real capital of Europe but now it feels like London is the place."
It is easy to get caught up in the giddy atmosphere in London, but the Olympics have been a summer sideshow for many.
"The thing about the London games is that everything seems to have gone well," said Tyson Barker, head of transatlantic relations at the Bertelsmann foundation in Washington.
"And that means no one is talking about it. If it had been a fiasco it would be a different matter."
Britons now talk of little but sport. The country has enjoyed its most successful performance at an Olympic Games for over a century, a tonic during seven lean years of austerity.
The Games have also helped transform what was long a forgotten and polluted corner of East London.
Stratford, home to the Olympics and one of the poorest parts of the capital, now boasts Europe's largest urban shopping centre and excellent transport links to the rest of the capital.
The apartments where the athletes have lived for the past few weeks will be converted into flats for sale next year.
Athletes will return to the Olympic stadium in 2017 for the world championships and Britain is also bidding to hold the world cycling championship in the velodrome in 2016.
Local soccer team West Ham United are the best known of four potential tenants for the stadium, built at a cost of 430 million pounds, and would give the area a focal point.
Manchester City moved into the stadium built for the 2002 Commonwealth Games and have become Premier League champions thanks to an infusion of cash from Abu Dhabi.
West Ham's "I'm Forever Blowing Bubbles" theme tune rang around the arena in one of the more parochial moments from Danny Boyle's opening ceremony. That may have pointed the way towards a viable sporting legacy for the venue.