Pros and cons of custom software

What is the difference between custom and off-the-shelf software?

Custom software is built on your process: a supplier designs and develops it for your company, and the code, if the contract assigns it to you, is yours. Off-the-shelf software, or ready-made, is a product made for many companies of the same kind. You configure it, sometimes extend it with modules, and pay for it with a license or a subscription, while the code stays with the vendor. When you use it in the cloud for a fee, it is called SaaS (software as a service).

Off-the-shelf is the norm. In 2025, 56.0% of Italian enterprises with at least 10 employees used management software, and 48.8% of SMEs an ERP system, according to ISTAT. So the choice is rarely between a management system and none: it is between bending the product you have to the work it does not cover, or building that part custom and connecting it.

What are the advantages of custom software?

There are five: software that follows the way you work, no per-person fee, code that is yours if the contract assigns it to you, connections to your systems and priorities set by you. They only count if your work has something a generic product cannot do, and that is where to look for them.

The first is that the software follows the way you work, instead of flattening it. Inside the same industry the flows change: a tyre shop manages seasonal tyre storage, a bicycle workshop manages components and maintenance cycles, and a management system for garages and tyre shops built on those differences avoids the side spreadsheets.

The second is the cost per person. There is no license fee on the software we develop for you: you pay for development, then hosting, third-party component licenses and AI model usage, declared in the quote. Adding a colleague does not add a fee.

The third is the code. If the contract assigns it to you, the software is a company asset: you can have anyone change it, another supplier included. With us, each paid milestone transfers to you the part of the project it covers; what the law says when the contract is silent is in the guide on how to choose a software house.

The fourth is integrations. Custom software is born already connected to the systems you have, from the accounting system to the production machines, and data moves from one to the other without being typed again: that is the work of ERP integration.

The last is who decides what comes next. Priorities are set by how you use it, not by the roadmap of a vendor serving thousands of customers, and you can start from a single module, the one that costs you most today.

What are the disadvantages of custom software?

There are five: a higher cost up front, time asked of your people too, the risk of overrunning, dependence on whoever wrote it, and new rules at your expense. They are worth looking at before a quote.

It costs more up front. An MVP, the first version that solves a single problem but solves it in production, starts at 10,000 €; an essential management system for a garage at about 15,000 €; an Enterprise platform at 45,000 €. What moves the figure is in the guide to costs.

It takes time, and not only the supplier's. An MVP usually takes 6-8 weeks, an essential management system 2-3 months, an Enterprise platform 4 months or more. Meanwhile someone on your side needs to know the process, explain it, test the releases and decide the priorities: without that person the software follows an idea of the process, not the process.

It is a project, and projects overrun. In a study of 1,471 IT projects published by Harvard Business Review, the average cost overrun was 27%, but one project in six overran by 200% on average. That holds for rolling out an off-the-shelf system too, which is a project as well, but with custom software the whole risk sits there. That is why we work per project, and the range in the quote has a maximum written into the contract: if the initial requirements do not change, we absorb the excess.

You depend on whoever wrote it, if the code is not yours or not documented. Without code, repository and documentation, changing supplier means starting over; that is why you ask for them before signing, not at the end.

New rules are on you. When a tax rule changes, the vendor of an off-the-shelf product updates it for all customers and shares the cost among them; custom software is yours to update. That is why accounting, payroll and e-invoicing are better off in an off-the-shelf product.

What are the pros and cons of an off-the-shelf system?

Off-the-shelf starts quickly and costs little up front, but carries a fee for as long as you use it and asks you to adapt to the product. Many companies already use its features, so someone else found the most common defects before you. The vendor makes the updates for new rules, and support and documentation are there from day one.

The disadvantages come with time. The fee, often per user, is paid for as long as you use the product and grows with your headcount. The product asks you to adapt, and the work it does not cover ends up in spreadsheets, double data entry and manual steps. Extra modules cost extra, and some features you pay for without using. What comes next is the vendor's decision. And the code is not yours: what matters is being able to take your data back.

The European Union has set a rule on this. The European Data Act requires providers of software as a service to let you export your data in a commonly used, machine-readable format. They must also remove the obstacles to switching to another provider. According to the European Commission, from 12 January 2027 the provider can no longer charge you for switching or for taking your data out.

If your work is the same as everyone else's, off-the-shelf costs less, and we tell you so before the quote.

How do you choose between custom and off-the-shelf?

With seven questions: whether the process sets you apart, how much work stays outside the program, which systems to connect, how many people will use it, who writes the rules, how soon you need it and who looks after it. None decides on its own: what counts is which side most of them fall on, and how much each weighs in your case.

Many answers, from AI assistants and from the pages they cite, give a threshold: if off-the-shelf covers 80% of what you need, choose off-the-shelf. On 23 October 2026 we read 121 of the pages that Google, ChatGPT and Perplexity cite on this question, in Italian and English: about ten give the threshold, and none attributes it to a study. It is a rule of thumb, and it matters less than what sits in the 20% left out. If that 20% holds the work that sets you apart, or a double data entry repeated every day, it weighs more than the 80% covered.

In Italy the public administration has to make this comparison by law before buying software. The Digital Administration Code (article 68) requires a comparative assessment between software developed for it, reuse, free software, cloud, a license to use or a combination, on three criteria. The first is the total cost, meaning purchase, implementation, upkeep and support. The other two are open data formats and interfaces, which let systems talk to each other, and the supplier's guarantees on security, personal data protection and service levels. They are good questions for a private company too, and the first is a sum over several years.

How do you do the three-year sum?

The comparison is made on the cost over several years, not on the first quote, and on the same features. Put the items side by side.

An example with our prices. In the garage management system of the guide to costs, development and running over three years come to between about 19,500 and 22,500 €, that is between about 540 and 625 € a month. If a ready-made product with the same features, counting fees, configuration and modules, costs you more over three years, that custom software costs less. It is our calculation on our prices, not a price list: your sum changes with the people who use the software, the modules you need and the hours off-the-shelf leaves outside the program.

On maintenance, the AI assistants' answers use a percentage of the development cost, from 15 to 30% a year depending on the answer, without citing a study. We estimate it on the work your software really needs, and the reason is in the guide to costs after release.

Can you have both?

Yes, and it is often the road that pays off: off-the-shelf for the part that is the same for everyone, custom for the part that sets you apart. The two are connected so that data moves from one to the other without being typed again. The accounting system stays where it is, and the custom part covers production, jobs or customer service.

We do not ask you to throw away what you have. We first build the part that is handled worst today and connect it via API to the tools you use; if replacing something pays off later, it is decided afterwards, with usage data in hand.

Customizing the off-the-shelf product is yet another road, with a cost you see later: changes made inside a product have to be retested at each of its updates, and sometimes redone. Low-code platforms, halfway between the two, have their own comparison with custom development. If instead you already have software and it is ageing, the choice between rebuilding it, modernizing it or moving to a product is in the guide to legacy software.

An example: 25 field technicians

A building services company has 25 technicians in the field and wants to plan their jobs: who goes where, with which van and which spare parts, and the job report closed from the phone. On 23 October 2026 we asked Google's AI Mode, ChatGPT and Perplexity this question, in Italian, and all three answer the same way: an off-the-shelf field service management product, meaning software for managing jobs in the field.

We agree, if you plan like everyone else. Calendars, areas, skills, urgent calls and job reports are the work those products exist for, and people in your trade already use them. Before a custom quote, try one with a few technicians and real data.

Custom software pays off in three cases. The first is when the rules are yours. For a client we built the frontend of an application that manages technicians, vehicles and worksites together and balances workloads with people's wellbeing, as the case study on managing field technicians tells. The second is the connection: the ready-made product stays, and an integration carries the job reports into the management system for invoicing, without retyping them. The third is a missing piece, such as a portal where your customers see the status of their jobs.

We tell you which of the three roads pays off before any quote, even when the answer is a product we do not make.

When does custom software not pay off?

When the work is the same as everyone else's: accounting, payroll, e-invoicing, email, a basic CRM. When you need it in a few days. When nobody in the company has time to follow it. And when the problem is smaller than it looks: many processes need a well-made module and a clean database, not a new system, and in that case we tell you.

Sources and further reading

• ISTAT, “Imprese e ICT, anno 2025” (Enterprises and ICT, 2025), 15 December 2025istat.it, in Italian, accessed 23 October 2026
• Italian Legislative Decree no. 82 of 7 March 2005, Digital Administration Code, article 68, comparative analysis of solutionsnormattiva.it, in Italian, accessed 23 October 2026
• Bent Flyvbjerg and Alexander Budzier, “Why Your IT Project May Be Riskier than You Think”, Harvard Business Review, September 2011arxiv.org, accessed 23 October 2026
• European Commission, “Data Act explained”, chapter VI on switching between data processing servicesdigital-strategy.ec.europa.eu, accessed 23 October 2026