How does inventory work for bundles and kits?

A bundle has no stock of its own; its availability is derived from its components. Selling one has to decrement every component, and the quantity you can promise is set by whichever component runs out first. Pre-assembled kits are different — those are built in advance and held as their own SKU with their own count.

Treating a bundle as a stocked SKU is how the same component gets sold twice, once inside the bundle and once on its own, with nothing connecting the two counts.

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