If you take out a loan to purchase a rental property, you can claim the interest charged on that loan, or a portion of the interest, as a deduction. However, the property must be rented, or available for rental, in the income year for which you claim a deduction. If you start to use the property for private purposes, you cannot claim any interest expenses you incur after you start using the property for private purposes.
Similarly, if you take out a loan to purchase land on which to build a rental property or to finance renovations to a property you intend to rent out, the interest on the loan will be deductible from the time you took the loan out. However, if your intention changes – for example, you decide to use the property for private purposes and you no longer intend to use it to produce rent or other income – you cannot claim the interest after your intention changes.