Writing the brief a manufacturer can actually quote against

A quotation is priced from assumptions, so supply them

Behind every price sits a set of guesses about batch size, scrap allowance, inspection level, packaging, material grade, finish, test coverage, delivery frequency and who carries components. If you do not state these, the shop assumes whatever makes its number competitive, and you compare offers built on different foundations. Set out the assumptions you want quoted against and ask candidates to price any alternative separately rather than silently substituting it. The same discipline exposes scope you had not thought about: someone has to unpack, someone has to store, someone has to dispose of rejects, and each of those has a cost sitting in a quotation somewhere.

Say which characteristics matter, and say why

A specification that treats every requirement as equally important tells a manufacturer nothing about where to spend effort. Mark the features that carry function, safety, regulatory weight or customer-visible appearance, and explain briefly what fails if each drifts. Engineers on the other side use that to choose process routes, fixturing and inspection frequency intelligently rather than uniformly. It also changes how deviations get handled once you are in production: a shop that knows which dimension governs assembly will call you about that one, while a shop treating the drawing as a flat list will either escalate everything or nothing.

Anything subjective needs a physical reference, not an adjective

Colour, gloss, texture, weld appearance, print registration, surface blemishes, sound and smell all cause disputes, because words such as clean, uniform or premium mean different things to a buyer and a production supervisor separated by distance and language. Provide physical limit samples showing acceptable and unacceptable extremes, agree who holds the controlled copies, and record how they are replaced when they fade or wear. Where a measurement instrument exists for the property, specify it and its method. The cost of not doing this is a shipment nobody can adjudicate, with your customer waiting and both sides certain they are right.

Describe the volume profile you actually expect

An annual quantity conceals almost everything a planner needs. Say how the demand arrives: a slow launch ramp, seasonal peaks, promotional spikes tied to your customers, or steady replenishment. Say how firm each part of that horizon is and how much notice you can give. Manufacturers price differently against a smooth profile than a lumpy one, and the honest ones will tell you which pattern their plant handles well. Inflating the forecast to obtain a better price is a common and self-defeating move: the price is set against volumes you then fail to deliver, and the renegotiation happens when you have already committed tooling.

Declare what is not yet decided

Design maturity varies, and there is nothing wrong with quoting an unfinished product provided everyone knows it is unfinished. State which elements are frozen, which are under test, and where changes remain likely. A brief that presents an evolving design as final produces a firm price that dies at the first engineering change, followed by an argument about who should pay for it. Naming the open items lets the manufacturer flag which of them would affect tooling, which affect only programming, and which they would prefer to see resolved before committing anything expensive.

Frequently asked questions

How much of our design should we send before anything is signed?

Send what is needed to price the work and no more. Overall envelope, materials, critical characteristics, process family, volumes and acceptance requirements are usually enough for a credible quotation. Detailed source files, firmware, formulations, process recipes and full assembly documentation belong later, once confidentiality terms are agreed and the shortlist is short. Staging disclosure this way costs you almost nothing in quotation accuracy and materially reduces how much of your product sits with companies that will never build it.

Should engineering or purchasing own the brief?

Engineering owns the technical content, purchasing owns the commercial frame, and one named person owns the document. Problems arise when the two halves are assembled separately and contradict each other, typically a specification demanding one inspection regime while the commercial terms assume another. Have both sides read the whole package before it goes out, and have the same pair review the responses, because a technically strong quotation with unacceptable terms and a commercially attractive one with technical gaps look identical on a summary sheet.

What if we only have a physical sample and no drawings?

Say so explicitly instead of letting the sample imply a specification. A part copied from a sample carries every accident of how that sample was made, and the shop will decide for itself which features are intentional. Either commission dimensional documentation as a defined piece of work, with agreement on who owns the resulting data, or specify by function and let the manufacturer propose the details. What you must avoid is an unstated assumption that the copy will match in properties nobody wrote down.