There are benefits to buying a new property such as high depreciation deductions, no renovation work needed, lower costs for repairs and maintenance since everything is brand new… but that doesn’t mean they are always the best option.
Often you can pay a premium for a new property and if it is part of a large complex or a development it will lack scarcity and have many other similar properties hitting the market simultaneously, possibly causing a drop in the asking rent in the initial stages.
Sometimes (depending on the developer) many new properties can be built on mass production, affecting the quality of the fixtures, fittings and finishes and/or have poor floor plans and room sizes.
Older properties are generally located in more established areas, can be solidly built and provide the ability to add value through renovations. This can lead to strong capital growth, increases to your rental return and depreciation allowances. The choice is always yours.