Mike Cannon-Brookes wasn't taken seriously for his first home purchase. He was for his latest

When Mike Cannon-Brookes was house-hunting in Sydney’s inner west for his first home, he didn’t feel real estate agents were taking him seriously.

Maybe it was his youthful looks, or the fact that at 24 he was only a few years out of university, but either way he enlisted the help of a buyer’s agent to take the pressure off the whole process.

“I really didn’t know anything about buying a property, and I didn’t want to be ripped off,” Cannon-Brookes told the Sun-Herald at the time.

Ultimately, he paid $840,000 for a three-bedroom apartment in a converted warehouse in Lilyfield in 2004, and sold it two years ago for $1.46 million.

Fourteen years later, Sydney’s real estate agents take any property queries from Mr Cannon-Brookes very seriously.

And so they should. At 38, the tech billionaire and co-founder of software giant Atlassian has bought Australia’s most expensive residence, securing Australia’s first nine-digit house sale for the Point Piper estate Fairwater of the late Lady (Mary) Fairfax.

The $100 million purchase ended 117 years of Fairfax family ownership and finally put to rest speculative reports the estate was to be gifted to the people of NSW after Lady Fairfax died.

Perhaps more importantly for Cannon-Brookes and fashion designer wife Annie, it put him next door to the $71 million house of his best mate and Atlassian co-founder Scott Farquhar and his investment banker wife Kim Jackson, and created a beachfront holding of 1.8 hectares where the two couples plan to raise their young families.

But even before Cannon-Brookes snapped up the trophy estate he was already being taken seriously by eastern suburbs agents.

A few days after his 31st birthday in 2010, he bought a former furniture emporium warehouse conversion in Paddington, known as House of Desks, for $7.3 million, and five years later sold it for $10.4 million to buy Centennial Park’s most expensive house Braelin for $12 million.

That Centennial Park record was smashed by Braelin again earlier this year when Cannon-Brookes sold it for $16.5 million.

It was his more recent trophy home pursuits that caught the attention of every real estate agent in Double Bay.

Having looked at some of the finest homes on the market in recent years – think the Rona and Barford estates in Bellevue Hill – Cannon-Brookes was credited with also single-handedly pushing up house values near the beach in Double Bay, given a few recent acquisitions and rumours he was circling homes on the beachfront.

The acquisitions included a 1936-built house known as SeaDragon for $7.05 million in 2016, followed by a semi for $9.1 million this year and last month a $17 million mansion, Verona. As for those rumours he was circling homes on the beachfront, Double Bay’s home owners might regret not taking the young rich lister’s passing interest in their real estate more seriously.