The cheaper offer leaves fixture design and making to us, while the fuller one includes design but not manufacture; our toolroom has no capacity estimate for either version yet.

Ask who supplies the accepted manufacturing drawings and who owns the complete fixture check in each option, then have the toolroom price the actual work and capacity against that split

Toolroom priced both splits and the required outside work; purchasing chose the fuller supplier for a defined paid design stage, with manufacture, installation and acceptance costs separately estimated, so we have a next step without pretending the whole cell price is fixed.

Keep the stage deliverables beside its price, including what your toolroom receives and who accepts it, so finishing that paid design does not simply produce another customer-scope blank