Building and then renting out a new home can be an effective way to invest. You can take advantage of better capital depreciation with a new home, as you can claim deductions over the maximum life of the property.
If you buy the right sized block which is eligible for subdivision, you could build more than one home and really start to develop your property portfolio. You could save time and potentially money by building more than one home at once, or by building in a certain position on your block to allow for future development. Each council will have their own rules and regulations about subdivision, so make sure you do your homework.