Straight-line depreciation from what a component cost new, how old it is and how many jumps it has. Three separate estimates - container, main, reserve - because they depreciate on different clocks. No account needed.
Harness and container. Reserve and main are priced separately below.
Estimated value
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Reline history and water landings move this number more than age does.
Estimated value
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Repack count, deployment count and rigger inspection history all bear on value.
Estimated value
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This is straight-line arithmetic, not an appraisal. It does not know the brand, the model, the repair history or what the same rig is fetching in your region this month - and those routinely matter more than age.
Sanity-check the number above against all of these before you buy or sell:
Gear determines whether you walk away. Have anything you are buying inspected by a certificated rigger before it is used, whatever this page says it is worth.