With the listing describing only a generic “Apple 12v dc (Other)” and no specific model, the A$500 asking price is hard to benchmark against the typical used market; without knowing whether this is a rare Apple IIc internal supply, a custom Apple TV 12v mod, or an obscure accessory, you can’t call it a bargain, fair, or overpriced yet. In the used Apple hi-fi/power niche, isolated 12v DC units for known models usually trade between A$30–A$80 unless they’re vintage computer internals or custom conversions, so A$500 is ambitious unless the item is a documented, rare original or a high-end custom build.
Before buying, confirm the exact model, voltage tolerance, current rating, connector type, and whether it’s original or modified; if it’s a genuine Apple IIc or early Mac power brick in clean, original-owner condition with the correct cable, it could be worthwhile for collectors, but if it’s a generic buck-booster or a DIY Apple TV 12v mod, the price is unjustified. Only proceed if the seller provides clear photos, specs, and proof of compatibility, because paying A$500 for an unknown 12v unit is risky unless rarity or originality is verified.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.