David Hallett, Victorian State Manager of Archicentre, the building advisory service of the Australian Institute of Architects, said when people do the figures on the cost of moving and all of the related government taxes such as stamp duty, there is not much change from $50,000 to $60,000 for which they receive nothing.

"For many home owners the renovation of the family home is a major way of building their superannuation and retirement funds as well as having some time to enjoy living in a better quality and healthier environment.

"Whilst renovation costs at this stage are remaining reasonably static, the major challenges for renovators and owner builders is to ensure that they get the design of the renovation correct to ensure it delivers a sustainable lifestyle on budget.

"For new houses and major renovations, the cost structure is approximately 46% on materials, labour 33%, and 21% on fees, levies, permits, taxes, and GST. The cost will vary for country areas adding 5% to 15% to the renovation."

Mr Hallett said the biggest challenge renovators and owner builder's face is getting their original design right, gaining competitive tenders, which can reveal up to 50% variance in costs, and managing the project to deliver the quality paid for, on time and on budget.

Archicentre is often asked for help when people have started renovations and then realised they needed to review their plans when they discovered, for structural or aesthetic reasons, the plan was not delivering the desired outcome requiring a costly redesign.

Without a well planned design and management approach to a renovation people may find the returns they were hoping for are severely eroded by unplanned costly variations during the construction stage.