They say money changes everything - but David Kaltschmidt and his wife Maureen Smith clearly have other ideas when it comes to their $328 million windfall.

Despite pocketing the biggest Powerball jackpot in history, DailyMail.com can reveal the frugal couple have changed almost nothing about their everyday lives.

Their three-way share of the record $1.56 billion prize propelled the pair into the ranks of America's super-rich with more than enough funds for yachts, supercars and sprawling mansions.

Instead, they have shunned the high-life by staying put in their modest $300,000 Florida home, frequenting the same shops and restaurants as before - and even continue to play Powerball.

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Modest millionare: Maureen Smith, 71, wheels her reusable grocery bag to her Tesla outside the Publix where she and her husband scored the winning Powerball ticket in January 2016

David Kaltschmidt, 56, upgraded his SUV when he won the lottery. He opted for a slightly newer model - a gold GMC Yukon Denali

Before: This was how the couple's house was when they won the lottery - but they did not move to a lavish new spread or spent their fortune on cars and yachts. They still have the same boat and have simply upgraded to a new SUV

Spot the difference: The couple did some upgrade work instead of moving house, with a fresh paint job for their home

What a win: When Florida's lottery secretary Tom Delacenserie (left) handed Maureen Smith, 71, and David Kaltschmidt, 56, their check, which would be paid over 30 years, they opted for the lump sum on the basis of their age. But they seem to have made little dent in their winnings

'They have hundreds of millions burning a hole in their pocket but it's almost as if nothing has changed,' dished a friend. 'They are as conservative as ever.'

Old habits die hard for Maureen, 71, who still does the weekly shop and chats with checkout staff in the same Publix where she bought the winning ticket 18 months ago.

'She even buys a Powerball ticket from time to time,' an employee told DailyMail.com. 'I guess it's just for fun - it's not as if they need the money.'

Ex-engineer David, 56, promised to buy himself a new car after going public in February 2016 to collect a lump sum payment before taxes of $327.8 million.

Locals in Melbourne Beach, Florida may have been expecting a Ferrari or top of the range Cadillac but the sensible retiree traded in his gold-colored SUV for a newer, but near-identical, gold SUV.

David uses the 15ft Boston Whaler he owned before the lottery win. The couple hail from Central Islip on New York's Long Island but moved to Melbourne Beach in 1991

The Powerball generated $114 million for public schools in the state of Florida. Maureen and Davis scored the winning ticket along with two other couples

Normal routine: Everyday life has not changed for the couple, who live in the same $300,000 home as they did before the record windfall

And despite having enough capital to afford a fleet of yachts, the keen fisherman still takes to the water in the same 15ft Boston Whaler he had parked up in his driveway before his life-changing win.

The couple's one splashy outlay is a $90,000 Tesla in matching gold for Maureen. It also has a vanity plate.

As for the remaining hundreds of millions friends and neighbors can only speculate on where it's being spent.

When DailyMail.com caught up with Maureen last week and asked what she's been doing as a newly minted multi-millionairess she smiled and said: 'Oh nothing exciting.'

'Taking care of family,' she added, before politely declining to speak further about her windfall.

Originally from Central Islip on New York's Long Island, David and Maureen have been married 37 years and moved to sleepy Melbourne Beach on the Florida coast in 1991.

Maureen continues to shop at the local Melbourne Beach Publix. The couple kept their win a secret for a month, even from their adult children

When DailyMail.com approached Maureen last week to ask what the couple has done with their hundreds of millions of dollars, she politely said: 'Oh, nothing exciting,' then added 'Taking care of family'

In addition to upgrading their SUV, the couple bought a gold $90,000 Tesla Model S

Maureen, a homemaker and former Avon Lady, has two grown up children: 50-year-old Michael who still lives in Long Island and Denise 47, who lives in the UK. She and her husband picked the same random set of lottery numbers - 4 8 19 27 34 with a Powerball of 10 - for three decades before landing the huge prize with two other tickets.

On the advice of lawyers they kept the win secret for a month, even from Michael and Denise, before telling them on the eve of the announcement. In their ensuing press conference David said the thought of having millions of dollars had given him sleepless nights and he had lost 10lbs from the stress.

'Instead of designing airplanes, I'm going to be doing charities and tax strategies and investments,' he said, giving the merest of hints about his spending plans.

Each winner had to choose between a $328 million lump sum or their entire $528 million delivered in 30 annual payments. Like fellow winners John and Lisa Robertson of Munford, Tennessee, and Marvin and Mae Acosta of Chino Hills, California, David and Maureen opted for the one-off payment because of their age.

Their neighbors told DailyMail.com they never expected to see them return to their neatly-kept three-bedroom home because of security concerns. However the down-to-earth pair opted to stay put at their ranch-style property on the banks of the Indian River, with sociable Maureen regularly seen calling on friends and walking her Pomeranian dog Cassie.

'I expect the winnings have been invested carefully for their family's future, but their money is their business and I would never ask about it,' said a neighbor living opposite, giving his name as Jim.

'But there's no luxury yacht moored out the back and no real changes. They were nice, humble people before and they are exactly the same now - although I've never asked them for anything.

John and Lisa Robinson immediately claimed their prize and even went on the Today show before they turned in their winning ticket to lottery organizers (John, right, Lisa, second left)

'It makes a nice change from all the stories you see in the news about people winning the lottery, going mad, even killing themselves.'

David and Maureen's huge jackpot win also benefited others. The Publix store received $100,000 for selling the winning ticket and the Powerball generated $114 million for schools in the state of Florida.

Fellow winners John and Lisa Robinson, of Munford, Tennessee, showed less restraint and claimed their prize immediately, even going on the Today show before they had handed their winning ticket to lottery organizers.

Marvin and Mae Acosta, meanwhile, took six months to come forward, finally breaking cover in July last year to claim their share of the spoils. They later released a statement saying they were dedicating nearly all of the prize money to charity, describing the win as 'rare gift that has been placed in our care.'

They bought their ticket in China Hills, a suburb of Los Angeles, but it is not know if they are from there. Their identities were revealed because Californian law mandates that winners be named, but they have not been photographed.