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Quoting faster: how trades businesses prepare their offers with AI

Writing a quote often takes more time in the trades than the work on site would suggest in advance. Take the measurement, look up line items, extrapolate quantities, insert NPK texts, maintain prices, show VAT correctly, lay it out. And all of this in the evening after the working day, because during the day the business is running. Anyone who quotes slowly loses jobs to whoever is faster. AI can shorten this preparation part considerably. But it does not take responsibility off your hands, and that is the honest core of this article.

The path from measurement to quote

In most businesses, preparing a quote runs through five steps. Each of them takes time, and this is exactly where automation comes in.

  1. Take the measurement. On site or from plans: areas, lengths, quantities, the layout of the space.
  2. Define the work. Which tasks are involved, in what order, with what materials.
  3. Assign line items. In Swiss construction this usually means selecting the matching NPK line items from the catalogue or working through a given bill of quantities.
  4. Calculate. Multiply quantities by unit prices, add material, labour, surcharges, discounts, VAT.
  5. Format and review the quote. Mandatory details, period of validity, payment terms, layout.

AI can prepare steps two to five: suggest line items from a description or a voice memo, extrapolate quantities from the measurement, insert standard texts and generate a clean document. Step one, the measurement itself, and the final review stay human. A wall that is measured incorrectly remains a wall measured incorrectly, even after a perfect calculation.

What AI handles and what it does not

The dividing line matters in the trades, because an error in the quote goes straight into the money. Calculate too low and you pay extra; too high and the job is gone.

What AI reliably prepares today:

  • Derive structured line items from a specification or a voice memo (“living room, 5 by 4.5 metres, paint walls and ceiling”).
  • Assign existing NPK or CRB line items to a description and read a bill of quantities.
  • Extrapolate quantities from measurements (areas, lengths, counts).
  • Suggest material from the stored catalogue.
  • Show the VAT at the correct rate and format the document.

What AI does not handle and should not:

  • The technical judgement of whether a line item even fits. A wrong NPK line item looks correct in the document and is still wrong.
  • The on-site measurement. No model detects measurement errors.
  • The margin. What your hourly labour is worth is your decision, not a language model’s.
  • The decision whether you quote on a binding basis or give a cost estimate. That is a legal and business question.

A realistic picture on accuracy: providers and field reports from German-speaking markets cite hit rates for AI-assisted calculations in the order of around 85 to 90 per cent with deviations below five per cent, where the remaining cases mainly concern unusual requirements not reflected in the data. These figures come from providers and are not an independent measurement. Treat them as an indication, not a guarantee. This is exactly why the final review step stays with a human.

Swiss specifics: NPK, SIA and VAT

Anyone quoting in the Swiss trades operates within their own set of rules. A generic AI from the internet does not know these details on its own; they have to be supplied to it as a data basis and as rules.

NPK, CRB and VSS. The Standard Item Catalogue (NPK) is the standard reference for uniform specifications in the Swiss construction industry. It is not published by a single body: the CRB is responsible for the areas of building construction, underground construction and building services (heating, ventilation, air conditioning, plumbing, electrical), while the VSS (Swiss Association of Road and Transportation Experts) publishes the chapters for civil engineering. The NPK comprises around 200 chapters spread across ten chapter groups (000 to 900). Because it is structured and machine-readable, it works well as a data basis: AI can read a bill of quantities and suggest the matching line items. The assignment still has to be checked, however, because a wrongly chosen line item flows directly into the price.

SIA Standard 118. It governs construction contract law specifically for the building sector and closes gaps that general contract-for-work law in the Code of Obligations leaves open. Important for quotes: SIA Standard 118 can become part of the contract if it is referenced and adopted in the tender or quotation documents. What is in your quote therefore has consequences for the later contract. That is not a detail an automated system should decide on its own.

VAT. Since 1 January 2024 the following rates have applied in Switzerland:

RateLevelTypical application
Standard rate8.1%Most trade services and goods
Reduced rate2.6%Everyday goods (e.g. food, medicines)
Special rate3.8%Accommodation

For trade services, the standard rate of 8.1 per cent is relevant as a rule. A company becomes liable for VAT from an annual turnover of CHF 100,000 in taxable services. There is no statutory obligation to show VAT separately on the quote, but it is common practice in the industry and advisable nonetheless: state clearly whether prices are inclusive or exclusive of VAT.

This distinction is easily overlooked in the rush, and it has real consequences. Under the Swiss Code of Obligations (Art. 3 to 5), a quote with an acceptance period is in principle binding for as long as the period runs. If you do not want to be bound, you need a clear reservation such as “subject to change” or “without obligation” (Art. 7 of the Code of Obligations).

With a contract for work there is a second level. A precisely calculated quote with fixed prices is binding, and the customer does not then have to accept price deviations. A cost estimate with an approximate price is not binding to the same degree: according to doctrine and case law on Art. 375 of the Code of Obligations, an overrun of around 10 per cent is generally still considered acceptable as a rule of thumb. If an agreed approximate price is exceeded disproportionately, the client may withdraw from the contract. Which form you choose is a deliberate decision on your part, not one made by an automated system in the background. An AI that simply generates “the quote” without anyone setting this course creates risk in exactly this spot.

What is already running at Vollmer Labs and what is not yet

Here is the honest state of things. The components needed to prepare a quote are running in production for us, but not yet in a finished live case for plumbing or painting/plastering.

  • rfqbuddy.com is our RFQ tool for structured enquiries and quote drafts. In its currently publicly visible form it is shaped as a platform for LED signage, not as a generic trades quoting tool. What interests us here is the mechanism behind it, reading, structuring, assigning, drafting, which is exactly what quote preparation requires.
  • CPA accounting agents we use in our own practice every day in production at a US accounting firm. This is an internal operating fact of ours, not a publicly verifiable reference case. It shows us that AI agents run reliably in a rule-bound, numbers-critical environment when rules and review steps are defined cleanly.
  • jeffri.ch is our AI for kitchen studios, with Swiss hosting in Zurich and a Swiss data protection link, in operation as a pilot. A related task: preparing structured line items and a quote from a recording.
  • ballistic.club is another live platform and evidence that we do not just plan products but operate them.

What this means for a plumbing or painting business: the individual components exist and are tested, but the solution has to be calibrated to your specific line-item catalogue, your prices and your trades. We are not selling you a finished off-the-shelf industry solution, because honestly it does not yet exist in precisely this form. What we can do: adapt the running components to your business and introduce them step by step, with the human review step firmly built in. You can find more on how we automate processes, and what that means specifically for plumbing businesses as well as painters and plasterers, on the respective pages.

— — FAQ

Frequently asked questions

Can AI send a finished quote without review?

No. AI can prepare the draft: derive line items from the measurement, assign NPK texts, calculate quantities and format the VAT. The technical and legal responsibility, however, stays with the business. Before a quote goes out, a specialist checks quantities, prices and assumptions. A binding quote under Swiss contract law cannot be delegated to an unsupervised automated system.

Does AI understand NPK and CRB line items?

Yes, provided the line-item catalogue is available as a data basis. The Standard Item Catalogue (NPK) is structured and machine-readable, which works in AI's favour. It is published by the CRB (building construction, underground construction, building services) and the VSS (civil engineering). AI can read a specification or a bill of quantities and suggest the matching line items. The assignment still has to be checked, because wrong items go straight into the cost.

What is the difference between a cost estimate and a binding quote?

A precisely calculated quote with fixed prices is binding. A cost estimate with an approximate price is not binding to the same degree: according to doctrine and case law on Art. 375 of the Swiss Code of Obligations, an overrun of around 10 per cent is generally still considered acceptable as a rule of thumb, and in the event of a disproportionate overrun the client may withdraw from the contract. Which form you choose is a business decision, not a technical one.

Is this worthwhile for a small business yet?

It depends on how many quotes you write per month and how similar they are. Anyone quoting a few highly individual projects gains less. Anyone calculating many comparable jobs with recurring line items saves noticeable time in the preparation. Honestly: in plumbing and painting/plastering the individual components are running for us, but we do not yet have a finished live case in precisely these trades.

Where does your business lose hours every week?

Tell us — in a free 30-minute consultation or by message. Reply within 24 hours.