How much does custom business software cost? Realistic prices and what drives them

The spreadsheet five people edit at once has become a business system. Someone overwrites a column, nobody knows which version is current, and the month-end report takes two days. So you ask for quotes for a proper application, and they come back at €15,000, €60,000 and €150,000. For what sounds like the same thing.

They are not the same thing. Each supplier has quietly assumed a different scope. This article gives you the ranges, the factors that move the price, and the questions that make quotes comparable.

Three sizes, three prices

Software is priced in days of work. The table converts days into euros at an example day rate of €800, which is close to the average freelancer rate in Germany, Austria and Switzerland (€103 an hour, according to the Freelancer-Kompass 2026). Agencies usually charge more, nearshore teams often less. Multiply the days by the rate in your own quote.

Size	What it typically is	Days of work	At €800 a day
Small internal tool	One process, a few screens, one or two user roles. Replaces a shared spreadsheet: equipment servicing, approvals, a simple order log.	15 to 40	€12,000 to €32,000
Business application	Several connected processes, roles and permissions, reports and exports, one or two integrations (ERP, email, accounting).	60 to 150	€48,000 to €120,000
Larger system	A customer or partner portal, many integrations, migration of years of old data, strict availability and security requirements.	200 and more	€160,000 and more

These are orientation figures, not a quote. But if one offer is five times cheaper than the others, it almost certainly describes a smaller system than the one you have in mind.

What drives the price

The number of screens matters less than people expect. These matter more:

• Integrations. Every system the application talks to (ERP, webshop, bank, email) adds days, and an old system with no API adds many. More on that in our article on connecting systems instead of retyping data.
• Roles and permissions. “Everyone sees everything” is cheap. “The regional manager sees only their region and approves up to €5,000” is not.
• Reports and exports. Each report your finance team needs in an exact format is a small project of its own.
• Old data. Moving ten years of spreadsheets and an old database into a clean structure often takes longer than building the screens.
• Availability and security. An internal tool for ten people and a portal for your customers need very different levels of protection, monitoring and testing.
• Changing your mind. The most expensive factor of all. A requirement changed after it was built costs several times what it would have cost on paper.

From idea to production

A good project does not start with a six-month build. It starts small and gets real users on it early:

1. 1 to 2 weeksWorkshop: the process, the users, what is a must and what can wait
2. 4 to 8 weeksFirst version covering the core process only
3. 2 to 4 weeksPilot with real users and real data
4. RolloutData migration, training, switching off the spreadsheet
5. After launchImprovements in small steps, based on how people actually use it

Paying per phase also limits your risk. If the first version shows the idea does not work, you have spent a fraction of the budget, not all of it.

The costs after launch

The build is a one-off. These are not:

• Hosting. A small business application on Azure typically costs from a few dozen to a few hundred euros a month, depending on users and data. More in our article on cutting Azure costs.
• Updates. Each .NET LTS version gets security updates for three years. After that, the application has to move to a newer version. Our .NET end of support dates list shows when each version runs out.
• Changes. The business changes, so the software does too.

Our rule of thumb: reserve 15 to 20 % of the build price per year for maintenance and small changes. An application nobody looks after for five years ends up like the ones in our article on what an old application really costs.

Ready-made or custom?

Custom software is not always the right answer. Often a standard product is cheaper and better.

	Ready-made product	Custom application
Start	In days	In weeks or months
Up-front cost	Low, then a licence per user	Higher, then maintenance
Fit	You adapt to the product	The software adapts to your process
Integrations	What the vendor offers	Whatever you need
Ownership	The vendor owns it	You own the code

Buy when your process is standard: accounting, payroll, CRM for a normal sales team. Build when the process is what sets you apart from your competitors, or when it has to connect systems that no product connects.

How to get quotes you can compare

Send every supplier the same short brief:

1. Describe the process, not the screens. Who does what, in which order, and what goes wrong today.
2. List the integrations. Which systems, and whether they have an API.
3. Say who uses it. How many people, which roles, internal staff or customers.
4. Split must-have from nice-to-have. The first version should contain only the must-haves.
5. Ask for an estimate in days per phase, not just a total.
6. Ask who owns the code. It should be you, from day one, in your own repository.
7. Ask what happens after launch. Who maintains it, how changes are billed, and how quickly urgent bugs get fixed.

For a larger project, turn this brief into a full software requirements document.

Whether to sign at a fixed price or pay for the time worked is a decision of its own, covered in fixed price or time and materials.

If AI is part of the plan, our article on what introducing AI costs breaks down that part separately.

How we work

This is exactly what we do. ProCoding is a .NET studio in Split, Croatia, and we build business applications in .NET, Blazor and Azure, on systems companies genuinely depend on, from calibration software for Bugatti Rimac to a travel platform. We work remotely on Central European Time.

We start with a free 30-minute call. We look at the process you want to cover and tell you honestly whether to build, buy or leave it in a spreadsheet for now. If building makes sense, you get an estimate in days per phase, and the code is yours from day one.

Sources

• Freelancer-Kompass 2026: Stundensätze fallen erstmals seit Jahren, freelancermap, 17 March 2026
• .NET and .NET Core support policy, Microsoft