Nearly two million struggling homeowners will be hit by higher mortage rates by the end of the year as a result of "Tory economic vandalism", Keir Starmer fumed.
And people who want to buy their own homes face an extra four years of saving, the Labour leader said - as he aimed a savage dig at Rishi Sunak's pool.
The floundering PM came under fire over the impact of Liz Truss and Kwasi Kwarteng's disastrous economic meddling last year.
He was told that aspiring homeowners now have to save an average of £9,000 more - which takes most people around four years to set aside.
"They think it's funny," Mr Starmer fumed, before pointing out this sum is "roughly the annual bill to heat his swimming pool".
The Labour leader told the Commons at PMQs that 850,000 people are currently paying higher rates following last year's Tory chaos, which sent markets into turmoil and mortgage rates soaring.
This is set to rise by a further 930,000 by the end of the year, MPs were told.
The Labour leader said: "Nearly a million people are paying more on their mortgages each month, because his party used their money as a casino chip."
He added: "By the end of this year nearly two million home owners will be counting the cost of the Tory economic vandalism."
This has dragged the average deposit up by £9,000 - which would take the average saver four years.
Mr Starmer, who branded the PM "out-of-touch" continued: "Four years for the average saver to save £9,000 - or to put it a different way in terms the Prime Minister will understand, roughly the annual bill to heat his swimming bill."
He was referring to a new pool at Mr Sunak's Yorkshire mansion, installed despite his local public swimming pool battling against closure.
It emerged in March that the multi-millionaire PM had splashed out tens of thousands to connect the heated private pool to the National Grid.
Mr Starmer said the Prime Minister's decision to scrap housing targets is "killing the dream of homeownership for a generation"
He said: "Every week, whatever the topic he stands there and pretends everything is fine across the country and every week he does so, he reinforces just how out of touch he is.
He added: "£9,000 would take four years, they think it's funny... roughly the annual bill to heat his swimming pool, but for most people, four more years of scrimping is a hammer blow to their ambitions and now he's kicking them when they're down, because his decision to scrap housing targets is killing the dream of homeownership for a generation. Why doesn't he admit he got it wrong and reverse it?"
Mr Sunak replied: "I promised to put local people in control of new housing and I'm proud that that's what I've delivered within six weeks of becoming Prime Minister.
"Now he wants to impose top-down housing targets, he wants to concrete over the greenbelt and ride roughshod over local communities. Now previously he did say, he's on record as saying local people, local communities should have more power, more control. Now he's U-turned, just another in a long list of broken promises."
The bruising exchange came less than 24 hours before voting opens in local authority elections.
The Tories are predicted to lose just 250 council seats on Thursday as Mr Sunak is set to escape an election drubbing.
Senior party figures had feared up to 1,000 of their councillors would be ousted in the PM’s first big electoral test.
But latest forecasts show the party’s losses could be limited to just a couple of hundred seats.
Electoral Calculus, which is a member of the British Polling Council, predicts the Tories will forfeit 258 council seats and finish the night with a total of 3,043 in the areas contested.
According to its forecast, Labour is on course to gain 408 councillors, leaving it with a total of 2,487.
When the seats were last contested in 2019, Theresa May had a catastrophic night losing 1,330 councillors.
