Start with the scope, not the supplier list
A PCB-only order and a complete product build require different information. List each deliverable: fabricated boards, populated assemblies, cables, enclosures, loaded firmware, test results and packaged units. For every item, identify its revision, owner and acceptance criterion. This scope becomes the basis for comparable quotations.
Understand the service models
In a consigned build, you supply some or all of the materials. In a turnkey arrangement, the manufacturer procures the agreed materials as well as carrying out assembly. Hybrid arrangements split the BOM between customer and supplier. None of these labels settles who owns excess inventory, approves alternatives or absorbs changes in component availability; those points belong in the written agreement.
Make quality measurable
Replace requests such as “high quality” with an agreed inspection standard, product-specific test coverage and records to be delivered. Identify which failures can be detected by visual inspection and which require electrical or functional testing. Agree the process for deviations, rework, rejected material and corrective action.
Control the transition to production
Use a prototype to answer design questions and a pilot build to check production assumptions. A successful prototype does not by itself prove that work instructions, fixtures, material supply and operator training are ready for repeat production. Record the open issues and the owner responsible for closing each one.
At a glance
| MODEL | CUSTOMER RESPONSIBILITY | POINT TO CLARIFY |
|---|---|---|
| Consigned | Supply agreed materials and design data | Shortages, attrition and material condition |
| Turnkey | Approve design, BOM and substitutions | Inventory, sourcing and purchasing terms |
| Hybrid | Identify the split by BOM line | Handover, accountability and missing parts |
| Box build | Define complete product requirements | Mechanical, firmware and final-test ownership |
A practical checklist
- Identify exactly what will be delivered.
- Freeze a common data revision before comparing quotes.
- Separate one-time costs from recurring unit costs.
- Agree how material substitutions and design changes are approved.
- Define test coverage, records and product acceptance.
- Document tooling, inventory and intellectual-property ownership.
Assign an owner to each open item and keep the decision with the project revision. A checked box should point to a document, approval or piece of evidence; it should not simply indicate that a topic was discussed.
A common mistake to avoid
Comparing unit prices without comparing scope. A lower price may exclude boards, functional test, programming, tooling or packaging. Use a single quotation comparison sheet and ask each supplier to identify exclusions.
Put the guidance to work
Start with the RFQ preparation checklist, keep component information in the BOM template, and compare evidence using the supplier scorecard. Confirm project-specific requirements with your design team and manufacturing partner.
Explore the related manufacturing scope or return to the EMS & CEM Basics guide hub.