The cost of Wembley has shot up by £550m. So who's netting the extra cash?

All over or just beginning? The jury was still out last night on the staggering escalation in costs for the new Wembley stadium. At £750m, it will become the most expensive arena project in world sporting history when the Football Association finally sends in the bulldozers.

The "absolutely final green light" – after almost six years of doubts, back-tracking, political recriminations, new designs, re-designs and designs on scrapping the whole venture – was expected yesterday morning. Instead, as the day dragged on and countless television crews and reporters spent a day in north London getting cold and bored instead of the story they sought, the only announcement coming from the FA's Soho Square headquarters was "maybe later". A neat summary of a farcical saga if ever there was one.

The hold-up, according to the FA, was "one or two last-minute details" in the mountains of paperwork that make up the 42 major documents that will finally allow the new 90,000-seat home of English football to be built. Some 18 individual contracts worth more than £20m each – covering everything from construction to catering to security to ticket sales – have had to be minutely scrutinised before being signed off.

"The 42 documents will be signed today," an FA spokesman said. A press conference, probably today, possibly tomorrow – perhaps never, at the current rate – should, in theory, confirm every last detail. (Expect to hear that the new Wembley will be a state-of-the-art stadium with better views and more leg-room than any stadium in the world. It will set new records for the number of escalators and toilets and set new standards for the quality of its corporate hospitality packages. It will take 39 months to build and should be open by early 2006, with its first major event being the FA Cup final of that year).

But whether the FA is prepared to be 100 per cent transparent on every aspect of every deal remains to be seen.

How, for example, can a stadium that was originally estimated to cost £200m back in 1996 now be costing £750m (or £560m more than Cardiff's Millennium Stadium)? Which firms of lawyers, consultants, designers, bankers and contractors have profited from the increase? Wembley National Stadium Ltd, the FA subsidiary in charge of the project, has strenuously denied that £80m-plus has already gone in legal fees alone. But will a comprehensive breakdown ever be produced?

Will the venue pay for itself? Who will make up the shortfall, if not? Adam Crozier, the chief executive of the FA, said as recently as last year, when the FA was contemplating paying for the lion's share of the stadium itself, that "the scale of the commitment would put our own future in jeopardy".

The FA, indirectly through loans and directly through start-up equity, is still expected to be shouldering almost £600m of the cost, so how is it more capable of doing so now? Has the FA budgeted for a steep decline in its own revenues, which, given the prevailing climate in football finances, is quite possible before the stadium is even open in 2006? Beyond these fundamentals, how much will it cost ordinary fans to watch matches? Will the FA guarantee now how much it will charge in 2006 and beyond? To date the FA has declined to answer any of these questions.

The facts as they stand are these. When Wembley was chosen, in December 1996, as the site for the new stadium, beating off early bids from Birmingham, Manchester, Bradford and Sheffield, the cost was put at "around £200m", although the price of land was not included.

The Wembley site was purchased with Lottery money in April 1998 and a month later Ken Bates, the chairman of Chelsea FC, was chosen as the chairman of Wembley National Stadium Ltd. By July 1999, when the first detailed plans were unveiled, the cost of the project had risen to £475m. This included the land acquisition (£120m), construction (£326m) and design and development (about £29m).

The first major hiccup came in November 1999 when Kate Hoey, who was Sports minister at the time, legitimately questioned whether the stadium would be fit to host athletics, as it was obliged to be under the terms of its Lottery funding. In December that year, Chris Smith, who was Secretary of State for Culture, Media and Sport, ordered the stadium to be redesigned as a home for football and rugby only, with athletics removed from the equation. Planning permission was eventually granted by Brent Council in June 2000.

In September 2000, the Australian construction company, Multiplex, signed a contract to build the new stadium for a maximum price of £326.5m but plans to open the stadium by 2003 were put on hold. In October 2000, Wembley staged its last football match, with England losing 1-0 to Germany. Wembley National Stadium Ltd then announced that the total cost of the new stadium might rise to £660m. This was touted as a "worst-case scenario" and included potential costs for delays, extra interest repayments due to the elongation of the project and mothballing the stadium until the bulldozers moved in. Mothballing alone was estimated at £2m per month.

The City, not least the bankers Chase Manhattan, got the jitters, saying that they were having extreme difficulty in trying to raise the £410m now needed. By December, the estimated overall costs had risen to £715m, although a detailed breakdown was never made public. By February 2001, Mr Bates had quit and been replaced by Sir Rodney Walker.

In May last year Mr Crozier said the project was doomed unless the Government stepped in. Patrick Carter was subsequently appointed as a troubleshooter. In October, after his assessment was handed in, the Culture Secretary, Tessa Jowell, told the FA to decide whether it wanted a stadium or not. In December the FA decided it did, at Wembley. Provision for athletics was back in the design.

At the end of May this year, the FA and Wembley National Stadium Ltd, with a streamlined board, convinced the Government it was ready to proceed. The FA signed "heads of agreement" with West Deutsche Landesbank for a £426m loan. That money, plus £150m from the FA, plus the original £120m Lottery money, plus £40m from local and central government for infrastructure, plus an expected £14m from Wembley National Stadium Ltd, makes the £750m needed. The current costs, broken down, are understood to be £352m for construction, £120m for land, about £50m for infrastructure, £23m for demolition, £40m for "development" (design, re-design and mothballing), and £80m for rolled-up interest between now and completion of the stadium. Which leaves about £85m for other fees and "contingencies", as yet to be explained. Soon. Maybe.

BIG EARNERS AT THE REBUILDING OF A NATIONAL EMBLEM

The architects and designers

Who: Lord Foster of the HOK Sport architectural consultancy.

Role: Lord Foster's track record includes such praised buildings as Hong Kong and Stansted airports. HOK Sport is the merged partnership of HOK and Lobb. Lobb worked on the McAlpine Stadium in Huddersfield, the Reebok Stadium in Bolton and Stadium Australia.

What will they make from Wembley? Lord Foster's consultancy can be expected to take a sizeable chunk of the £40m design and development costs.

The construction company

Who: John Roberts, the straight-talking chairman and founder of Multiplex.

Role: The Australian construction firm that built the West Stand at Ken Bates's Chelsea FC. Questions were raised over the transparency of the tendering process that led to Multiplex being awarded the contract for the stadium but the Football Association and the Government were happy to proceed.

What will they make from Wembley? Multiplex will be paid £352m to build the new stadium.

The corporate ticket broker

Who: Mark McCormack, founder of the sports marketing group IMG.

Role: Mr McCormack's company has offered to guarantee the Football Association around £32m a year, long term, in return for all the rights to the new stadium's estimated 17,000 corporate seats, corporate boxes and suites.

What will they make from Wembley? It is estimated that corporate income from the stadium could be £40m a year, which could represent an annual profit of £8m.

The banker

Who: Robyn Saunders of German bank WestLB.

Role: Saunders led the team which put together the £426m loan which forms the bulk of the funding. The idea is to pass on at least £300m to other creditors, leaving WestLB with about £100m exposure to the project.

What will they make from Wembley? WestLB will have been paid for arranging the loan and will hope to turn a profit by passing much of it on to other parties. Their return will form much of the £85m total paid to bankers and lawyers.