We're used to seeing properties auctioned off with the price growth - and the seller's profit - in mind. But sometimes the money is destined for another purpose.

That's the case with 66/551 Elizabeth Street, Surry Hills, which is being auctioned to raise money for charity Hands Across The Water.

Started by an Australian forensic detective, Peter Baines, it runs orphanages for Thai children who lost their parents and families in the 2004 tsunami.

Bernadette Janson, the founder of The School of Renovating and renovator of 25 years, is the brains and talent behind the project.

Janson says she's an admirer of the Hands Across The Water, having raised money through charity bike rides in the past.

"I'm just really blown away by the organisation and how they actually do what they do. They've very transparent," she says. "Every cent we raise for them goes towards the kids - I think that's pretty impressive.

"They've just completely transformed those children's lives."

Janson bought the property for $475,000 in last June. She undertook the project with the help of some of her students, one of whom managed it. Janson worked with her son, an architect, on the design as well as with some tradies and retailers who donated their time and products.

And they're not the only ones pitching in - agent Con Fotaras of Belle Property Surry Hills is managing the sale for free, and Damien Cooley will be wielding the hammer on the big day, also without charge.

So far the response has been positive, Janson says. "We had one open [at the weekend] - Con said he had so many people there he had to stand in the corridor."

It's not the only organisation Janson has been involved in. She's also raised money for St Vincent de Paul, and was a board director for a not-for-profit charity for women with intellectual disabilities.

Renovating has long been a passion after she attempted her first job - painting and decorating her bedroom, aged 13.

"There's something about taking something really ugly and turning it into something really beautiful, it's really satisfying," she explains.

So what does the lucky buyer get, aside from contributing to the care of children in need? A light and modern one-bedroom, one-bathroom apartment in trendy Surry Hills, close to Crown Street, the Belvoir Street Theatre and Prince Alfred Park - complete with new floors, study alcove and private balcony.

The apartment will be sold with the appliances included, and Janson says if an investor picks it up and wants to keep the furnishings, they'll sell it to them at cost.

She has had her eye on this particular apartment building for a while, describing it as "really lovely", and speaking highly of the neighbours.

"Because I'm on the lookout for property all the time, I work quite closely with my agent. He knew I had my eye on that building, and this property came on the market just when I started working on this project."

66/551 Elizabeth Street, Surry Hills, goes up for auction on May 13 at 11am. It has a buyer's guide of $550,000.