How much custom software costs (and what drives the price)

"How much does a website cost?" or "how much is an app worth?" are questions with the same answer as "how much does a house cost?": it depends on what, what for and who builds it. But that does not help you decide. What follows is how the price of custom software development actually comes together and what ranges are reasonable.

What "custom" means and why it changes the price

Custom software is built for your specific process, instead of bending the way you work to fit a generic tool. That means analysis, technical design, development, testing and deployment tailored to you. It is not always worth it: if an off-the-shelf product covers what you need, it is cheaper and faster.

Custom development is justified when that process is part of your competitive edge, when market tools force you to pay for modules you do not use, or when integrating the systems you already have has become the bottleneck.

The factors that move the budget

• Functional scope. The number of screens, business rules and edge cases. A contact form and an admin panel with role-based permissions are not in the same league.
• Integrations. Connecting to a payment gateway, an ERP, a third-party API or a legacy system adds work and risk. It is where poorly planned budgets overrun the most.
• The state of what you already have. Starting from scratch is more predictable than working on old, undocumented code, where you have to understand it before you touch it.
• Non-functional requirements. Performance under load, security, accessibility, GDPR/LSSI compliance. They do not show up in the demo, but they are the difference between something that holds up in production and something that fails with real users.
• Who does it. A senior profile costs more per hour, but makes fewer expensive decisions and leaves behind code that can be maintained. A "cheap" build with no architecture and no tests gets paid for in full again the following year.

Reference ranges

As a guide for a small business or freelancer project, done with senior judgement and handing over the code:

Type of project	From	Note
Custom corporate or personal site	€900	Goes up with a CMS, multiple languages or dynamic sections.
Online shop (e-commerce)	€1,800	Depends on the catalogue, gateways and day-to-day management.
Native Android app	€3,000	Depends on functional scope and the backend.
Monthly software maintenance	€79/month	Depending on hours and guaranteed response time.

These are "from" figures: the real price always goes in a fixed proposal, with scope and timeline in writing, before starting.

The costs people forget when comparing quotes

• Maintenance. Live software needs dependency, security and compatibility updates. Budgeting only the initial build is budgeting half of it.
• Content and data. Migrating data, writing copy and preparing images takes time, whether it is yours or billed.
• Domain, hosting and services. Email, certificates, third-party services with a monthly fee.
• The cost of picking the wrong supplier. Rebuilding a badly done project costs more than doing it right once, because you also have to dismantle what came before.

How to ask for a quote you can actually compare

Give every supplier the same information: what problem you want to solve, which systems have to be integrated, what usage volume you expect and what timeline you are working to. Insist on a proposal with detailed scope, not a bare number. And be as wary of the quote that is triple the rest as of the one that is a third of it: one of them has not understood the project.

If you want a second opinion on a quote already on your desk, or to start from a review before asking for anything, tell me about the case.