Upvote:4
In general, the answer is no, personal goods that you take with you overseas are not subject to tax when you return to Australia (I'm assuming you live in Australia). Most of the time, there won't be a question about your personal goods. However, if for some reason you are carrying multiple similar items (eg. 3 laptops) or expensive equipment (eg. $20,000 video camera), then to be safe you should let Customs know about these items before you leave Australia.
See the Crossing the Border page for more details:
If you are departing Australia with expensive items (such as computers, cameras and video cameras) and you intend to bring them back to Australia, register these items on the B263 Goods exported in passenger baggage form (633KB PDF).
For the TRS part of your question, the following page appears to explain: Bringing goods back into Australia for which you have already claimed a TRS refund
If the total value of the goods you are bringing into Australia that you purchased overseas or for which you have claimed a refund under TRS is greater than your passenger concession:
- you must declare all of the goods
- you will need to repay the GST refund back on the goods you claimed under the TRS
- duty and GST will apply to all items purchased, not just goods over the limit of your passenger concession.
There is no mention of depreciated value of goods brought into Australia, even if you bought them before leaving.