Thank-you gifts have one job: signal genuine warmth without creating any obligation. The strongest picks are consumable, universal and inexpensive: a A$35 cold-pressed olive oil, a hand-poured candle, a single great coffee bag, a premium tea, a small jar of honey from a respected producer.
What to avoid: anything that requires the recipient to display or store it, gifts that imply you know personal details, oversized hampers (they read as transactional), and gifts above A$60 for a routine thank-you (they create awkwardness about reciprocation).
When to spend more: a teacher at end of year (A$30–A$60 is the polite norm in Australian schools, often pooled across the class), a neighbour who fed your cat for three weeks (A$60–A$100), a host of a multi-day stay (A$80–A$120 plus a card). For most thank-yous, the hand-written card carries the warmth; the gift is a small token alongside it.
Last-minute: an instant Mecca / David Jones / Simon Johnson e-voucher; an Endota Spa pass. We rank these specifically on 'comfortable to receive' — never on price.