1. Send the same enquiry package
Give each supplier the same drawing revision, material specification, quantities, required treatments, inspection requirements and commercial delivery basis. When suppliers quote different scopes, the lowest number may not represent the lowest finished-part cost.
2. Verify the scope of production
Ask which operations are in-house and which are subcontracted. Confirm responsibility for tooling, casting, machining, heat treatment, finishing and inspection. Request evidence relevant to your material and component instead of relying only on a general factory introduction.
3. Review tooling and sampling
Clarify tooling ownership, maintenance, modification costs and the sample approval process. Ask what happens when samples require a drawing or process change. Separate initial development timing from the proposed schedule for repeat orders.
4. Compare quality requirements
Check that the quote includes the inspection and documentation you need. Ask about material identification, drawing revision control, nonconforming parts and change notification. Verify any certificate and its scope directly rather than interpreting a logo as universal qualification.
5. Compare total delivered cost
Review casting price alongside machining, treatment, finishing, testing, packaging, transport and any applicable import costs. Confirm the currency, delivery term, payment schedule and quote validity. Do not compare an unfinished casting with a ready-to-assemble component.
6. Establish the working relationship
Agree the technical contact, drawing approval method, order confirmation process and communication expectations. A useful supplier explains assumptions and identifies open questions before production. Start with a documented sample approval and keep the accepted specification available for repeat orders.