Andy Burnham's promises and inherited black holes are estimated to cost the British taxpayer more than £250billion.
Such expenditure is enough to fund a Greater Manchester mayoralty contest 500 times over.
On Monday, the Downing Street hopeful set out his 10-year plan to fix the "broken" Westminster system and kickstart his "devolution revolution".
He also set out the plan to launch the largest council house building programme since the postwar period, which would come to an estimate of somewhere between £8billion and £13billion to build 40,000 homes each year.
The MP also is considering the reversal of Rachel Reeves's tax raid on National Insurance Contributions, which would cost between £16billion and £25billion per year.
Mr Burnham would also plan to nationalise water companies, which Whitehall predicted would cost £100billion.
Meanwhile some of his plans have a slighter small bill, with his bid to restore bus fare caps coming to between £150million and £250million per year.
In the end, the costs would come to around £250billion, according to analysis by Guido Fawkes.
But his plans were said to be turned on their head after Sir Keir Starmer failed to notify the Makerfield MP that he would have to scrounge for an extra £4.7billion in his first Budget for the Defence Investment Plan.
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Andy Burnham says he wants to 'maintain' London's status as 'the world's greatest capital city'
Andy Burnham is currently answering questions from Reddit users
| GETTYAndy Burnham says he plans to "free up London" in a answer to a question about devolution and "Downing Street North" plans.
The Makerfield MP said: "As I said in my speech on Monday, I want to free up London with even greater devolved powers so it can go to the next level and maintain its status as the world’s greatest capital city.
"This could include powers over education, skills and housing and more fiscal devolution.
"Downing Street North will be at the service of London and the South East in helping it take powers out of Whitehall, in exactly the same way as it will help the North."
Andy Burnham answering questions from Reddit
Andy Burnham is currently answering questions from users of the /r/ukpolitics forum on social media website Reddit.
We'll be keeping an eye on the Makerfield MP's answers and bring you the key moments as they happen here on the live blog.
Andy Burnham to woo Gen Z voters with 'major' tax breaks
Andy Burnham is eyeing up billions of pounds in tax relief to young people as the Prime Minister in waiting aims to woo Gen Z voters.
Allies of the Makerfield MP have suggested the likely next Prime Minister would introduce plans exempting young people from paying income tax for the first three years of full-time employment.
One Labour MP close to Mr Burnham told The Independent: "He is going to be a major offer to young people looking at education, employment, tax, public transport, rent to buy, helping them through their lives."
Another close ally said: "He has discussed an income tax exemption for the first three years of employment to help young people save for a deposit for a mortgage.
"It is the sort of imaginative idea he considers to look at how we can do things differently, to try and deal with the problems which nobody seems willing to solve.
“Obviously one of the issues about accessing mortgages is that many young people just cannot save for a deposit to get one. This could help break the logjam."
Liberal Democrats call for Harry Kane to be knighted
The Liberal Democrats have tabled a motion in Parliament for England captain Harry Kane to be knighted.
The motion, put forward by Lib Dem MP for Oxford West and Abingdon Layla Moran, says the Bayern Munich striker should be rewarded for his "World Cup heroics".
Ms Moran said: "Harry Kane has shown inspirational leadership and character on and off the pitch - championing the very values that make our country so great.
"If Andy Burnham wants to kick off his premiership on the right foot he should back my campaign. This is about bringing the country together. I hope every England fan encourages their MP to sign!
"Let’s get behind the lads for Mexico on Monday, and let's make sure Harry Kane comes home not just with the trophy, but with a well-deserved knighthood."
Downing Street says it will continue to use X despite Lisa Nandy's decision to move off platform
The Prime Minister previously accused Elon Musk of trying to 'whip up division' on X
| GETTYDowning Street indicated it would continue to use X despite the Culture Secretary’s decision to take her department off the platform.
Lisa Nandy announced she and the Department for Culture, Media and Spot (DCMS) would leave the Elon Musk-owned platform on Thursday, saying it “favours abuse and misinformation".
Asked about her decision on Friday, a spokeswoman for No10 said it was up to individual ministers and their departments whether they continued to use the platform.
The spokeswoman said No 10 kept its use of social media "under review", but gave no indication the Prime Minister would be following Ms Nandy in leaving X.
She added: "It is for individual departments to decide what is right for them in this regard.
"Our full focus remains on making sure X is following the law, cleaning up its act and ensuring it is safe for women, girls, children and people right across the country."
'New-builds should NEVER house asylum seekers,' Home Office vows
New-build should "never house asylum seekers", the Home Office has said, amid a row over a proposed "migrant street" in Shropshire.
A Home Office spokesman said: "New homes should never house asylum seekers.
"The Home Secretary has directly intervened to stop migrants being moved into the Stoke Heath development and no asylum seekers remain on site.
"Earlier this year, the Home Secretary introduced robust processes to ensure new-build sites can never be considered again."
Andy Burnham ally blasts 'out of touch' Keir Starmer over 11th-hour World Cup pub decision
Andy Burnham's ex-adviser has accused Sir Keir Starmer of being "out of touch with reality" over his last-minute decision to allow pubs to stay open into the early hours for England's World Cup match.
Sacha Lord, who served as Greater Manchester's first-ever Night Time Economy Adviser during Mr Burnham's time as Mayor, took aim at the Labour's treatment of the hospitality sector.
Yesterday, Sir Keir confirmed that pubs are permitted to remain open until 5am on Monday, July 6, with the game kicking off at 1am UK time.
Despite this decision, some of Britain's biggest pub groups have revealed only a certain number of their sites will be able to remain open for the match.
Labour General Secretary sets out timetable for departure with Keir Starmer due to step down in the coming weeks
Labour's General Secretary has set out her timetable for departure with boss Sir Keir Starmer due to step down in a few weeks' time.
Hollie Ridley said she would step aside from the top job after the party's Autumn Conference.
Her departure will coincide with a new leader after she was appointed to the position by the outgoing Prime Minister.
Andy Burnham to face YOUR questions amid row over dodging scrutiny - but will be able to pick and choose which ones
Andy Burnham is set to face an online grilling by the British public - but has stopped short of ensuring full scrutiny by picking and choosing the questions he will answer.
On Monday, the Labour leadership hopeful fell under fire for refusing to answer questions from furious lobby journalists following his first major speech as Makerfield MP.
After outlining his 10-year plan for No10, he sneaked out the backdoor of the People's History Museum in Manchester to dodge engaging with reporters.
And, later today, the former Mayor of Greater Manchester will be delivering much of the same in his "Ask Me Anything (AMA)" session, answering questions on social media website Reddit, where he and his team can select their preferred queries.
He will take questions directly from the 453,000 weekly readers of the r/UKPolitics sub-reddit, along with some of his 141,000 Instagram followers.
Many have accused Mr Burnham of potentially becoming Prime Minister without having faced the wrath of the media over policy issues which is normally delivered during general election campaigns.
It is feared the MP could be catapulted into No10 without a proper grilling and could trigger further calls for a snap national contest.
'Split time between No11 and the North,' Andy Burnham to tell new Chancellor
Andy Burnham is set to tell his Chancellor that they should split their time between No11 and the North as part of his "devolution revolution".
"Imagine if the Chancellor spent part of their working week based outside London. It would change their perspective," one source told the Telegraph.
Mr Burnham said he plans to spend at least one day in Manchester while Prime Minister.
Rishi Sunak, while Chancellor, drew up plans to send civil servants up to the north east in Darlington as part of the Tories' levelling-up agenda.
Andy Burnham 'really buoyed up' ahead of public grilling as Makerfield MP returns to Warrington
Andy Burnham has said he is feeling "really buoyed up" ahead of his public grilling as the Makerfield MP returned to his home in Warrington.
He said: "I'm feeling really buoyed up by the generous reaction to the speech I made earlier this week. It seems people do want a new direction in politics, a new way of doing things.
"More doing, less arguing. More power put into places like this."
He announced he would set out further details about his devolution plan "in the coming days".
Allies tease Boris Johnson could return to Westminster politics in bombshell comeback
Allies of the former Prime Minister have teased Boris Johnson could return to Westminster politics in a bombshell comeback.
One insider source claimed they could "see him campaigning properly at the next election".
Andy Burnham hints taxes will rise and dismisses 'crude' cuts to DWP benefits
Andy Burnham has dismissed the prospect of "crude" reductions to welfare spending while signalling that tax increases may be necessary to finance his policy agenda.
Earlier today, the likely incoming prime minister rejected what he termed "crude cuts" to Department for Work and Pensions (DWP) benefit payments.
When pressed on whether Labour's manifesto commitments and fiscal framework would remain intact, Mr Burnham confirmed they would, though he noted there remained "some room within that manifesto for movement on tax".
The former Greater Manchester mayor, who could enter Downing Street as early as July 20, insisted he maintained discipline on public finances despite accusations that his plans would necessitate higher taxation.
Keir Starmer pressured to change law to fast-track deportation of Pakistani child rapist
Sir Keir Starmer has been facing mounting pressure to change the law to fast-track the deportation of a Pakistani child rapist.
Shabir Ahmed, who was ringleader of a Rochdale grooming gang, was convicted of 30 child rape offences.
Despite being sentenced to more than two decades behind bars, he was allowed to walk free yesterday.
Paul Waugh, the Labour MP for Rochdale, and Jim McMahon, the Labour MP for Oldham, have demanded Labour search "every available avenue" to deport the criminal.
Yesterday, the Prime Minister asked Shabana Mahmood to see "what can be done" to deport the child rapist.
Andy Burnham grilling to take place online at 5pm
Andy Burnham's online grilling - where he will be able to pick and choose which questions he answers - will take place later this afternoon.
He beckoned his followers to join him on Reddit at 5pm for an "Ask Me Anything" session.
'Running away!' Culture Secretary and Lord Hermer quit X with parting rant at 'misinformation'
Culture Secretary Lisa Nandy has quit X with a parting shot at so-called "misinformation" on the platform.
The Labour minister announced her decision in her final of more than 10,000 posts on Elon Musk's social media site, adding that her department would also be leaving.
Ms Nandy wrote: "A platform originally designed for free speech and expression now favours abuse and misinformation over meaningful debate.
"It isn't healthy for our democracy or our communities and I don’t want to support it."
DCMS is the second department to leave the platform in a matter of days, after Lord Hermer told the Attorney General's Office to leave X over "racism and misogyny".