Datum
All skills
CostRev. Q3 2026

Supplier quote review

Compare supplier quotes on a normalized basis and build a should-cost baseline from material, cycle time, machine rates, and tooling amortization, so negotiation targets the padded line items. Use whenever the user receives machining, casting, molding, or fabrication quotes, asks why a quote is high, needs to compare suppliers fairly, wants a should-cost estimate, or is preparing for a price negotiation.

Marco Bellini portraitMarco BelliniCost Engineering ManagerXometry logoXometry

Likes are peer vetting. Like this skill if it held up in your work.

Supplier Quote Review

Normalizes quotes so they compare like-for-like, builds an independent should-cost, and identifies the specific line items worth pushing on, with the walk-away math stated.

Required inputs

  1. The quotes: unit price by quantity break, NRE/tooling, material assumptions, lead time, payment and shipping terms (EXW vs. DDP changes real cost), and any exclusions.
  2. The part: process, material and stock form, rough dimensions/weight, tightest tolerances, finish/coating/heat treat operations, and annual volume with expected program life.
  3. Context: current price if resourcing, target cost if one exists, and any constraints (approved vendor list, region, certifications like ISO 9001/AS9100/ISO 13485).

Method

  1. Normalize first. Put all quotes at the same quantity, currency, incoterms, and scope. Add missing scope to the deficient quote (inspection reports, plating, packaging) at estimated cost so the comparison is honest. A cheap quote missing the coating is not cheap.
  2. Should-cost build. Construct bottom-up:
    • Material: net weight plus scrap/buy-to-fly factor, at a current market price per kg for the grade; state the price source and date.
    • Process time: estimate cycle time from the features (setups, roughing volume, finishing passes, holes and threads) or molding cycle from wall thickness; multiply by a regional machine-plus-labor rate. State the assumed rate and region.
    • Secondary ops: heat treat, plating, and finishing at typical lot pricing with minimum-lot effects called out.
    • Overhead and margin: apply a stated assumption (commonly 20 to 40 percent combined) rather than hiding it.
    • Tooling: amortization check; verify the quoted amortized piece price against NRE divided by committed volume.
  3. Variance analysis. Compare each quote against the should-cost by line: where is the gap? Material price gaps suggest the supplier's stock assumption differs (ask for their material line). Time gaps suggest a different process plan (fewer setups on a 5-axis, or they see a problem the drawing hides). Big margin gaps at low volume often mean the supplier doesn't want the job at that quantity.
  4. Quantity-break sanity. Plot the quoted price vs. quantity; a healthy curve flattens as setup amortizes. Breaks that don't flatten signal setup cost being recharged, worth a direct question.
  5. Negotiation prep. Produce three things: the two or three line items with the largest defensible gaps, the design changes that would remove real cost (link to a DFM review when the gap is caused by the part, not the supplier), and the volume/commitment levers (blanket PO, multi-year, consigned material) that trade something the buyer can actually give.
  6. Beyond price. Score lead time, quality certifications, capacity risk, and single-source exposure alongside price, and state the landed-cost-adjusted ranking, not just the unit-price ranking.

Output format

  • Normalized comparison table: all quotes at common scope/quantity/terms, with adjustments shown
  • Should-cost breakdown table with every assumption visible
  • Variance table: quote vs. should-cost by line item, flagged where the gap exceeds roughly 20 percent
  • Negotiation brief: specific asks, supporting rationale for each, and the design-change alternatives
  • Risk notes: anything that makes the cheapest quote not the best award

Guardrails

  • A should-cost is an estimate with stated assumptions, not a fact; present gaps as questions for the supplier before treating them as padding.
  • Do not recommend sharing one supplier's quoted numbers with another; frame negotiation asks around the should-cost and target, which keeps the process clean.
  • If the lowest quote is more than roughly 30 percent below the cluster, treat it as a risk signal (scope misunderstanding, unsustainable pricing, or quality shortcuts) rather than a win, and list the verification questions.
  • Regional rates and material prices drift; date-stamp every market assumption and tell the user to refresh them if the review is reused later.