Sourcing · The total cost comparison · Element
The price
The unit price and what it includes.
The part
What it is
Prices are frequently not comparable because they include different things — delivery, packaging, tooling, minimum quantities.
Normalising to a comparable basis is the unglamorous work that makes the rest of the comparison meaningful.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.