One thing made of several: kits and assemblies

A kit is a way of saying “these three, sold together”. Nothing is made. What exists is the moisturiser, the lipstick and the perfume, sitting on the shelf under their own names. So a kit holds no stock of its own (it cannot, there is nothing to hold), and selling one takes those three off the shelf.

An assembly is a thing. Somebody physically built it from components, and once built it sits on a shelf being a table. It holds stock of its own, it is sold from that stock like anything else, and its recipe matters only on the day a batch gets made.

That single difference decides everything else: whether there is a build step, whether the item has a stock figure, and what happens when it ships. Getting it the wrong way round is how a table’s legs get counted twice: once when the table was built, and again when it was sold.

Set the recipe on the item once: four legs, one top, and the fitting service if you charge for one. Then Assemblies records each batch you actually make: what it consumed, when, from which warehouse, and what it cost.

Before it builds anything it checks every component. A batch short of one screw is refused whole: it will not consume the other eleven parts and leave you with no table and no screws either. Where a component sits in more than one bin and you have not said which, it asks rather than guessing, because emptying a bin somebody was keeping for another job is not a small mistake.

What a batch cost is worked out from what the parts were worth on the day and then left alone. Component costs move with every later purchase; what a table built in March cost is what its parts cost in March.

Deleting a batch puts everything back: components on to the shelf, finished goods off it. That is refused once the finished goods have been sold, because you cannot un-build a table that has been delivered.

No. Composite items are off until you switch them on in Settings › Business profile, and assemblies are a second switch beside it. A shop selling gift boxes wants the first and has no use at all for the second. Left off, nothing about your workspace is different.

No existing item, stock balance or movement was changed. Ordinary items behave exactly as they did, and an invoice for one moves stock exactly as it did.

There was a half-built idea of a “bundle” item type in the product that nothing ever read. No stock behaved differently because of it. Anything carrying it is now a kit, which is the one of the two that needs no build step.