The Block winners Courtney and Sev address cheating claims after record-breaking $1.87 million win as they reveal how they will spend the cash: 'We may need a mediator'

The Block besties Courtney and Sev came onto the series as best friends, survived months of gruelling renovations and walked away as the biggest winners in the show's history.

But after pocketing a staggering $1.87 million between them, the pair have admitted there could finally be something that puts their rock-solid friendship to the test - and it has nothing to do with dodgy tiling or disagreements over paint colours.

Speaking exclusively to the Daily Mail, the Brisbane-based reality TV winners joked that while their friendship did not strain during filming the Channel Nine renovation show, their first-ever bust-up could be over how they divide their enormous winnings.

'Actually, our first fight will probably be about the bloody split of the prize pool. That's where we might need a mediator,' they said.

The pair admitted they couldn't have done it without the support and guidance of co-host Scott Cam - joking that while they had eventually come to love him, there were times where his stern demeanour left them reeling.

'We got a few whoopings from Scotty! We were always in the doghouse with Scotty on Fridays... but on Monday he would be our friend again,' Courtney said.

'But there is absolutely no bad blood now. What happens on The Block stays on The Block! He said he is going to have us round for a barbecue.'

The pair also dismissed claims that they had 'cheated' their way to victory, insisting that any dishonest behaviour would have been made public.

'I would like to tell those people to politely go away! What we did was well within guidelines, we did everything fairly,' they said.

'If we were genuinely cheating, would Channel Nine have let that happen? No! They would have whipped us!'

Earlier in the season, the pair came under scrutiny for what the other contestants considered a 'dodgy' loophole to save money.

At the centre of the stoush was Courtney and Sev's 'custom artisan wine cellar rack', for which they paid just $14,500, while similar structures can cost as much as $100,000.

The other Blockheads were angered when they learned that the cellar was worth much more than the pair coughed up, but could be priced cheaply because it was deemed to be 'artwork'.

Anything classed as art is priced at the vendor's discretion, meaning that the cost can vary wildly.

'There is no retail price for it; it's up to the artist to price it how they see fit,' Sev explained.

'It's not up to us for you to figure out how to play the game and to know what to put in your garage to build that asset – that's not up to us'.

Fellow contestant Lisa confronted the pair, who insisted they weren't breaking any rules as everyone on the show has been finding these 'loopholes' in their renovations.

Learning that the cellar should have cost almost seven times more than Courtney and Sev paid, Lisa said: 'I know this deal is dodge.'

Flipping her middle finger in anger, she added: 'They know they're breaking the rules, but they're doing it with a twist.'

Jolene was equally enraged, firing off a string of expletives.

'Are you joking? If they win tomorrow, I'm going to call a body corp. F***ing smug c**s,' she ranted.

Despite ruffling some feathers, Courtney and Sev's trick paid off.

Guest judge Dave Franklin raved about the installation, calling it the 'best wine cellar' he had 'ever seen.'

Meanwhile, as for how Courtney and Sev are planning to spend their money, Courtney joked to the Daily Mail that there was one thing she was in the market for now she was $900,000 richer.

'I should buy myself a husband!' she said, while Sev cheekily added: 'We will probably have a lot more friends now!'

The pair made Block history during Sunday's grand finale, with their stunning $4.72 million auction result.

They entered the auction with a reserve of $3.45 million, but fierce bidding quickly sent their property soaring, leaving them $500,000 ahead of the next-highest profit.