How much does custom software cost? The short answer is that it depends; the useful one is four jobs I am often asked for, with their weeks of work and their price.
At the end of every month, the owner of an online shop did the same thing: he downloaded all the invoices that PrestaShop, the platform he sells on, had generated, and uploaded them to his accountant’s software so they could keep his books. Today that work does itself. The shop and the accountant’s software are in sync: every invoice goes out as soon as the order closes and, if a customer returns a purchase, the credit note is issued and sent without anyone stepping in.
An automation like that is built in one or two weeks and costs from €1,190 to €2,380, excluding VAT.
Whoever asks how much custom software costs usually gets the same answer: it depends. And it is true, it depends on the scope, on what the system has to do. But once the scope is defined, the price can be given and, in jobs like the invoices one, it is counted in weeks. Here are that one and three other real jobs, from the shortest to the longest, with the problem each one solved and what a job like it costs today.
Why the price is counted in weeks
I work in sprints. A sprint is one week of development with a specific goal and a fixed price, €1,190 excluding VAT. At the end of the week I deliver a piece of the system that already works; you handle it in a test environment and, with it in front of you, decide whether we carry on.
With that unit, quoting a job comes down to one question: how many weeks are needed. To answer it I study the case before starting and prepare a proposal, free and with no obligation, that puts the goal and the price of the first sprint in writing. The full method is on the custom software page.
Syncing the invoices is the smallest job of the four because it creates no program: it connects two that already existed. Whether it takes one week or two depends, above all, on the destination program. If it offers a documented way in, what the trade calls an API, one is usually enough.
An assistant that stays on call
A small travel agency organises routes for its clients, and on a route something can go wrong at any moment: the coach does not show up at the pick-up point, the hotel does not have the room ready. If the problem came up outside office hours, someone at the agency had to be on call to sort it out or find an alternative.
The job was an AI assistant that looks after the traveller at any hour. It receives the incident, handles it and, if need be, finds the alternative. Nobody at the office is on call any more.
A customer service assistant is solved in one or two sprints, from €1,190 to €2,380. The second one appears when channels have to be added, such as WhatsApp, or when it has to be linked to the business’s other programs. After delivery there remains the AI model’s usage, a small expense I break down in What an AI chatbot really costs.
A paper archive that answers on the spot
A law firm kept hundreds of thousands of documents on paper. Whoever needed a detail from an old case or a client went to the archive, looked for the file in the storeroom and came back. Each search, about 40 minutes.
The solution had two parts. The first, scanning everything. The second, building on top of those documents an AI assistant that answers the team’s questions: it locates in the archive the passages that bear on the case and writes the answer from them. The technique is called RAG, and its virtue is that the assistant answers with what the firm’s papers say, not with what the model thinks it knows. What used to take 40 minutes is now there on the spot.
An AI assistant for internal documentation needs between one and three sprints, from €1,190 to €3,570. Three things weigh on it: how many documents there are, what format they are in and who may see each one. A digital, well-ordered archive is less work than hundreds of thousands of scanned pages. And since this documentation is usually confidential, I work only with AI providers that commit to not training their models on it.
Goods in, without spreadsheets
In the warehouse of an e-commerce business, every delivery of goods followed the same script: the operators checked what had arrived, matched it against the delivery note and updated the stock in an Excel sheet. If something did not add up, with units missing, something broken, or the wrong product, they added a line in another Excel sheet.
Today an AI-powered system has retired both sheets. The operator scans the delivery note and records the incident, if there is one; the system updates the stock and sends each alert to the team that has to resolve it.
It is the longest job of the four. An internal application takes two to four sprints, from €2,380 to €4,760, because, besides doing the work, it has screens, users and permissions. Two sprints cover one complete flow; the rest come from connections with other programs, reports and profiles that see different things.
What makes a job longer
The four prices are ranges because two jobs of the same kind do not always need the same number of weeks. What pushes a job towards the top of its range is, almost always, one of these four things:
Integrations. Every program the system has to talk to adds work, and adds more if it offers no documented way in.
Legacy data. Bringing in years of records from spreadsheets or from another program means cleaning and checking them before they can be trusted.
Permissions. A system the whole team uses the same way is simpler than one where management, administration and the warehouse see and do different things.
Personal data. If the system handles customer or employee data, it incorporates what the GDPR requires, such as access logs and retention periods, and we sign the data processing agreement.
Work out your own case
With the estimator you can work out yours: pick a number of sprints and you will see the price, the timeline, the payment schedule and which of the four kinds of job fit within that scope.
Project sprints
€2,380
2 weeks of development · €2,879.80 incl. VAT
Payment schedule
At the start of sprint 1€1,190
At the end of sprint 2€1,190
€1,190
€1,190
€1,190
€1,190
Jobs that fit
Internal application2–4 sprints
Process automation1–2 sprints
AI assistant for internal documentation1–3 sprints
AI customer service assistant1–2 sprints
Above four sprints the work is a system with several modules or integrations, and the number of sprints is set in the proposal.
Sprints are billed in blocks of two: half at the start of the block and the other half at the end. A single sprint is paid in full before starting.
In all four jobs there was a specific task someone did by hand: downloading invoices, being on call, going to the archive, filling in an Excel sheet. As soon as that task was described, the work of replacing it could be measured in weeks, and weeks have a price. That is why, as long as there is no scope, custom software is neither expensive nor cheap: it cannot be priced yet.
Frequently asked questions
How much does custom software cost?
It depends on the scope, which I measure in one-week sprints at €1,190 each, excluding VAT. A simple automation fits in one sprint; an internal application takes between two and four (from €2,380 to €4,760); a system with several modules chains as many as it needs. The quote sets how many before starting.
What are some examples of custom software for businesses?
The four in this article are among the most common: the automation that moves data between two programs, the AI assistant that looks after customers out of hours, the one that answers from the company’s documentation, and the internal application that replaces spreadsheets. Order, booking and job-sheet managers are variants of the last one.
How long does it take to develop custom software?
Each sprint lasts a week, so the timeline matches the number of sprints. The jobs in this article run from one to four weeks, and at the close of each week you receive a part of the system that already works.
Who owns the code of custom software?
You do, always, also when the system is hosted on my servers. You receive the complete code with its documentation and, if you want it, the repository in your name.
What happens if the project needs more sprints than planned?
Every sprint has a fixed price and is approved before it starts, so you never pay for work you have not accepted. If the scope grows, I propose the additional sprints to you in writing, with their cost, and you decide whether we carry on.
Can we start with one part and extend the system later?
Yes, and that is the usual way. The first sprint solves whatever relieves the team the most; the following phases extend the system with the same method and at the same price per sprint.
