I often encounter misunderstanding when a taxpayer may claim interest on a build. Its a great example of why personal tax advice early is a must. Many taxpayers read / hear about the decision in Steele's case where interest on a build was allowed as the taxpayer was constructing property intended to be rented. This decision doesn't address other costs such as rates etc...The general view is these costs are NOT deductible. Also the interest if it is deductible should not be claimed as a rental item. It is claimed elsewhere on the return until the property becomes available to rent. Then there are taxpayers who are questioning - Will I sell or rent ? Steele's may not apply to them. Then there are many taxpayers who haven't heard about Steele's decision and consider the interest (and also other ownership costs) is deductible as incurred. Not necessarily. In many cases the whole of the cost of construction may be a capital cost and the whole sum is basically deferred and later offsets the sale (after GST ifs allowed for). Importance of 1. Determining your intent / changed intent at all times 2. Understanding GST timing & treatment 3. Diligent record keeping that supports tax and GST and assists apportioning for each build (ie profit on sale, QS report if kept, GST claims etc) 4. Co-ordination of all of the above for error free tax issues.