Short answer. An option model per product family: option groups with their values, dimensions with their limits, and derived quantities, area, perimeter, number of leaves, computed by the application. Constraints between options and dimensions, forbidden, forced, limited, evaluated on every change, which grey out the forbidden option and say why, instead of letting the impossible be promised. Price rules, per square metre, per metre, flat, percentage, tier, in a written order of application, with rounding and grids per customer, versioned; the price is a visible waterfall, not a number. A generated quote with dimensioned sketch, price lines, validity and versions, sent in two minutes; online acceptance with a deposit. And, from the same configuration, a generated bill of materials with lengths, bars and offcuts that gives the planned workshop cost and the margin before sending, a production order created on acceptance, and a fitting order. According to the common description, a configurator limits allowable options, validates their compatibility and integrates the choices into the product specification; it is exactly this construction.
This guide is for the maker of aluminium or PVC joinery, kitchens and wardrobes, gates and railings, signs and large-format print, furniture and blinds, the reseller selling these products made to measure, and the founder based in France whose diaspora customers want to configure and pay from Paris. It does not repeat how a pricing engine for unit products is built, described in the quote and invoice guide, nor how an order is made and costed, described in the manufacturing guide; it describes what is added when the product does not exist before the customer has chosen dimensions and options, and it extends our software engineering page.
Configuring a made-to-measure window
The figure follows an aluminium window configured at the counter. Rules run on every change, and the price is rebuilt.
Dimensions: 1,400 by 1,200 millimetres, entered or taken on site; the application computes the area, 1.68 square metres, and the perimeter, 5.2 metres, used by price rules and the bill of materials. Options: type, leaves, colour, glazing, accessories, each with its values. Constraints: one leaf is impossible because the width exceeds the maker’s maximum leaf width, 900 millimetres, and two leaves are forced; the roller shutter is allowed because the height is under 2,200. The forbidden option is greyed with its reason; it is not hidden, so the seller can explain it to the customer.
The price is built as a waterfall: the base per square metre, the colour surcharge as a percentage, double glazing per square metre, the insect screen as a flat amount, the roller shutter per metre of width; every rule is a visible line, the total is rounded by a written rule, and the lead time comes from the workshop load. The per-customer grids of the quote and invoice guide apply on top. Product, limits, options, prices and lead time are a constructed example; the limits are the example maker’s, written by them in the first week, not a standard.
«An option is not a line of text: it has values, constraints with other options and price rules, written once by the manager.»
One accepted configuration, four documents without retyping
The figure follows the same window after acceptance. The configuration is the single source, and nobody retypes it.
The quote: generated dimensioned sketch, price lines with visible rules, validity, bilingual PDF following the printing guide and the bilingual application guide, deposit payment link following the online payment guide, versions when the customer changes their mind, v1 white, v2 anthracite. The generated bill of materials: frame and leaf profile lengths, the number of six-metre bars by the maker’s offcut rule, glazings at rebate dimensions, hardware, shutter; it gives the planned workshop cost, 38,400 dinars, and so the margin, 38 %, before the quote is sent.
The production order is created on acceptance, with components reserved, following the manufacturing guide; the finished lot is linked to the configuration. The fitting order plans the technician in the customer’s zone, with before and after photos following the trustworthy photos guide, signature, and an equipment record created at the customer’s for warranty and preventive visits, following the field service guide. By hand: two hours and a variable price; with the configurator: two minutes, the same price, zero retyping. Configuration, lengths, costs and dates are a constructed example.
«The accepted configuration is the single source: the quote, the BOM, the production order and the fitting read it, nobody retypes it.»
Selling a made-to-measure piece, in six beats
Configuration is the accented beat: that is where the manager’s rules run, at the counter or on the rep’s phone.
Measure: dimensions are entered at the counter or taken on site by the rep, on their offline phone following the offline guide; area and perimeter are computed. Configure: options under constraints, the impossible greyed and explained, the forced ticked. See the price: the waterfall rule by rule, and the margin against the generated BOM, visible to the seller according to their rights in the roles guide.
Send the quote: dimensioned sketch, lines, validity, by WhatsApp and e-mail following the notifications guide; a new version at every change. Accept and collect: online acceptance, deposit, production order created; the customer in France pays in euros following the two-currency guide. Make and fit: the BOM and the order read from the configuration, fitting planned.
The configurator, in five layers
Constraints are the accented layer: without them, the configurator is a form that lets the impossible be promised.
Option model. Product families, option groups with values, dimensions with limits, derived quantities; declared by the manager in the application, not coded. Products and components come from the product record guide. Constraints. Rules between options and dimensions, forbidden, forced, limited, evaluated on every change, with a message per rule; tested on three past quotes before being opened to sellers. Price rules. Per square metre, per metre, flat, percentage, tier, in a written order, with rounding and grids per customer; versioned, and a quote keeps the version of its rules.
Generation. Quote with dimensioned sketch; BOM with lengths, bars and offcuts; production order; fitting order; one configuration, four documents, zero retyping. Channels and measurement. The counter, the rep’s offline phone, and an online configurator for the customer, with the same model and the same rules; quotes per day, quote time, acceptance rate, real vs planned margin, in the manager’s dashboard.
Six real situations, and what the application does
Every row is a sentence heard at a joiner, a kitchen maker or a sign maker, and the answer is a construction.
Three sellers, three prices: price rules are written once, and the same configuration gives the same price, whatever the seller or the channel. The quote takes two hours: two minutes of configuration, a quote generated with a sketch; the seller spends time with the customer, not with the calculator. The impossible was sold: a constraint greys the option and says why; a 1,400-millimetre leaf is no longer promised.
The margin is known afterwards: the generated BOM gives the planned cost and the margin before sending, and the manager sets a threshold below which the quote requires approval. The workshop retypes the quote: the BOM and the order read the configuration; a dimension is entered only once. The customer in France wants a quote: the online configurator, with the same model and rules, gives them the quote and lets them pay the deposit from Paris; the rep takes final dimensions on site before manufacturing.
Building a configurator in 2027, in weeks
Seven weeks, the first without code, and two for the model and constraints, because a missing rule sells the impossible.
- What the manager sees: price rules and constraints, written by them; the day’s quotes with their planned margin; quotes below the threshold awaiting approval; the acceptance rate.
- What the seller no longer does: compute, draw, write the quote, promise the impossible, retype dimensions for the workshop.
- What is measured: quotes per day, time from request to quote, acceptance rate, real vs planned margin per family, dimension errors in the workshop.
Week 1, rules: product families, options and their values, dimension limits, constraints and price rules, written with the manager and the workshop; three past quotes are recomputed by hand to serve as tests. Weeks 2 and 3, model and constraints: options, dimensions, derived quantities, constraints with messages, and the three quotes replayed until price and BOM come out right. Week 4, price and quote: waterfall, rounding, grids, dimensioned sketch, bilingual PDF, versions, acceptance and deposit.
Week 5, generation: BOM with bars and offcuts, planned cost, production order, fitting order. Week 6, channels: counter, offline phone, online configurator for the customer. Week 7, measurement: quotes per day, quote time, acceptance rate, real vs planned margin, Monday review. Going live follows the delivery guide: one product family first, with the most demanding seller, then the others.
- Why an option model and not a spreadsheet?
- Because a spreadsheet computes a price but refuses nothing: it lets a 1,400-millimetre leaf be promised. The option model carries values, limits and constraints, and it is what the quote, the BOM and the production order read. It is declared by the manager, not coded.
- Who writes the price rules?
- The manager, in the first week, with the workshop: per square metre, per metre, flat, percentage, tier, in a written order, with rounding. They are versioned, and a quote keeps the version of its rules. They change without development.
- How is the bill of materials generated?
- From the configuration: profile lengths come from dimensions and type, the number of bars from the maker’s offcut rule, glazings from rebate dimensions, hardware from options. It gives the planned workshop cost and the margin before the quote is sent, and becomes the production order on acceptance.
- Can the customer configure themselves?
- Yes, through an online configurator using the same model and rules as the counter; they get the quote and pay the deposit, including in euros from France. The rep takes final dimensions on site before manufacturing, and the final version replaces theirs.
- What if the seller wants a special price?
- They apply a discount in the waterfall, visible on the quote, according to their rights; below a margin threshold written by the manager, the quote requires approval. The rule comes from the quote and invoice guide.
- How many product families to start?
- One, the best seller, with three past quotes as tests. When price and BOM come out right on all three, the family opens to sellers, and the next one is prepared.
- How long to set this up?
- Seven weeks in the typical calendar, the first without code and two for the model and constraints. A maker who already has the pricing engine and the BOM of the manufacturing guide takes less; one starting from a calculator and Word takes all seven.