The Rosie Project author Graeme Simsion selling his Fitzroy family home

The stunning five-bedroom, three-bathroom house at 131-135 Gore Street features an internal tranquility pool, a spiral staircase leading to a library and a private roof garden.

When the couple bought the house about 17 years ago, Simsion said, it was derelict and unoccupied, so they kept the core structure and did a complete rebuild with the help of architects Teo and Perperis.

“We told them we wanted lots of light. They delivered, with glass in all directions and three big light wells,” said Simsion, who is expecting about $4 million for his home when it goes to auction on April 1.

“What we’ll miss most is the upstairs deck with views over the city — sitting up there with a glass of wine and a slice of tuna on the barbecue. And watching the fireworks on New Year’s Eve — we had about 30 [people] up there last year.”

And with three levels, including a spacious living room with double-height ceilings, the new owners would have plenty of room to entertain.

Listing agent Arch Staver, of Nelson Alexander, said it was one of the biggest houses to hit the Fitzroy market in terms of accommodation, flexibility and location.

“We don’t often have five-bedroom homes become available in Fitzroy,” he said, adding that the property also had a street frontage on Little Gore Street.

“This is a renovation that was done 15 years ago, and yet still remains very, very current.”

Mr Staver said the sale could challenge the highest priced house sold at auction in Fitzroy.

Last November, a four-bedroom balcony terrace at 17 Bell Street sold at auction for $4,011,000 — the highest house sale reported to the Domain Group. But higher prices have been achieved off-market.

The Gore Street property might set a suburb record, but it won’t be known until after the sale, Mr Staver said. 

Gore Street is home to some of the suburb’s most significant sales, including the former home of comedian Hamish Blake.

Simsion and Buist are now downsizing to an apartment two blocks away after having lived in the suburb for 27 years because their children, both in their 20s, are leaving home. 

Asked what was keeping them in the inner north, Simsion pointed to the mix of residential homes, restaurants, shopping — and people. Fitzroy also delivered some of the best things from their experience of living in New York, he said.

For Simsion, the room he used the most was not his home office — where he did a lot of his writing and editing — but in the kitchen.

“[The kitchen] works so well that we’ve specified an identical layout for our new apartment. Two ovens, two dishwashers, access to the barbecue, and just the right amount of separation from the breakfast and dining areas,” he said.

“I don’t write every day but I think about it – often over dinner with a glass in my hand, sometimes with my writers’ group workshopping ideas.

“I write wherever I am – and a lot of time that’s at home. A lot of my writing is rewriting – editing – and my place for that is in the downstairs front office, looking through the glass doors to the garden, with a big computer screen in front of me.”

Simsion and Buist, chair of Women’s Mental Health at Melbourne University and author of psychological thriller, Medea’s Curse, are attending book events around the world and working on their joint novel Two Steps Forward, due to be published in October.