Why Custom Software Instead of SaaS? Benefits for Businesses

Salesforce, HubSpot, Monday.com, Pipedrive — the market for business software-as-a-service (SaaS) is booming. According to Gartner, worldwide spending on SaaS is expected to exceed 300 billion US dollars in 2026. Yet more and more businesses are finding that off-the-shelf solutions do not fit their individual processes. In this article, we compare SaaS solutions with custom-developed software and show when a tailor-made solution really pays off.

The problem with standard SaaS

SaaS solutions promise a lot: quick setup, no installation, regular updates. In practice, however, many businesses run into fundamental problems:

Features you don't need

Typical CRM or project management tools offer hundreds of features — most businesses use only 20–30% of them. According to a study by ProductPlan, on average 80% of a SaaS product's features go unused. Even so, you pay for the whole package. The result: a cluttered user interface that confuses employees and makes onboarding harder.

Features that are missing

At the same time, the very features that would be crucial for your business are often missing. Your workflow differs from the standard? You need a particular report format? You need an interface to a specialised system? With SaaS solutions, you have to adapt — not the software.

Data protection and GDPR (DSGVO)

Many large SaaS providers — especially US-based ones such as Salesforce, HubSpot or Monday.com — store data on servers outside the EU. According to Bitkom, 78% of German businesses consider the GDPR compliance of cloud services to be problematic. With custom software, you decide for yourself where and how your data is stored — on your own server, in a German data centre or in a private cloud.

Cost comparison: SaaS vs. custom over 3 years

Probably the most important aspect: costs. At first glance, SaaS solutions seem cheap — but the monthly licence fees quickly add up.

Sample calculation: CRM for a small business (5 users)

Cost item	Salesforce Essentials	HubSpot Professional	Custom solution (Adlegio)
Monthly costs	€25/user = €125/month	€90/month (plus onboarding)	Individually calculated
Annual costs	€1,500	€1,080 + onboarding	Predictable, no licence fees
Costs over 3 years	€4,500	€3,240 + extras	One-off development + low-cost hosting
Setup / onboarding	€0–500	€500–3,000	Included in the project price
Customisation	Severely limited	Only via expensive integrations	Unlimited
Data storage location	USA (AWS)	USA / EU (selectable)	Germany / EU
Ownership of the software	No (licence)	No (licence)	Yes (your code)

Prices: Salesforce Essentials and HubSpot Professional, as of 2025/2026 (may vary). Custom costs at Adlegio are calculated on a per-project basis.

But the pure licence costs are only the tip of the iceberg. With SaaS solutions, there are frequently additional costs:

• Add-on costs: many important features are only available in more expensive plans or cost extra
• Integration costs: connecting to existing systems often requires expensive middleware (e.g. Zapier, Make)
• Training costs: complex systems such as Salesforce require certified consultants for setup (€80–200/hour)
• Price increases: SaaS providers raise their prices regularly — at Salesforce, increases have averaged 7–9% per year in recent years

5 advantages of custom software

1. 100% tailored to your own processes

The biggest advantage of custom software: it is developed precisely for your workflows. You don't adapt to the software — the software adapts to you. Every form, every workflow, every dashboard is designed in the way that is best for your business.

An example: a trades business does not need a sales pipeline with lead scoring and marketing automation. It needs simple customer management, scheduling, quotation and invoicing — all in one interface that the master craftsman can also use from a smartphone on the building site. That is exactly what custom software can deliver.

2. No monthly licence fees to third parties

With custom software, there are no ongoing licence costs controlled by external providers. You pay once for development and, on an ongoing basis, only for hosting and optional maintenance — costs that are typically well below SaaS licence fees and do not depend on third-party price increases.

According to Statista, businesses worldwide spend an average of 3,500 to 4,500 USD per employee per year on SaaS subscriptions. For a team of 10 people, that is 35,000–45,000 USD a year — a budget that, with custom software, often already finances the entire development.

3. Full data sovereignty (GDPR)

With custom software, you decide where your data is stored. On a German server, in an EU data centre, or even on your own server in the office. This considerably simplifies GDPR compliance and protects sensitive customer data from access by foreign authorities (keyword: US CLOUD Act).

For industries with special data protection requirements — healthcare, legal advice, financial services — custom software with full data sovereignty can even be a regulatory necessity.

4. Unlimited extensibility

Your business is growing and your requirements are changing? Custom software grows with you. New modules, new interfaces, new features — everything is possible, without having to wait for a SaaS provider's roadmap or relying on features the provider may never develop.

A typical scenario: you start with customer management, later add task management, then invoicing and finally a dashboard with key figures. With custom software, this is an organic process. With SaaS, you often have to switch to a more expensive plan or introduce a completely new tool.

5. No vendor lock-in

One of the biggest disadvantages of SaaS is vendor lock-in: once you have chosen a system and built your data, workflows and processes on it, switching to another provider is extremely time-consuming and expensive. According to a study by Flexera, 57% of IT decision-makers cite vendor lock-in as one of their biggest concerns about cloud software.

With custom software, you own the code. Your data sits in a database to which you have full access. If you want to change your hosting provider or have the software developed further by another developer, you can do so at any time.

When does SaaS make sense?

Despite the disadvantages mentioned, there are scenarios in which SaaS is the better choice:

• Very small teams (1–3 people): when the effort for custom development exceeds the budget and standard processes are sufficient
• Standardised processes: when your business uses established industry standards that are well covered by SaaS solutions
• Quick start: when you need to get going immediately and have no time for custom development
• Short-term projects: when the software is only needed for a limited period
• Evaluation: to test which features you really need before investing in custom development

When does custom software make sense?

• Special workflows: when your business has processes that no standard software covers
• More than 5 users: from this size upwards, SaaS licence costs often quickly exceed the development costs of custom software
• Long-term use: when the software will be used for years, the development costs pay for themselves compared with ongoing licence fees
• Data protection requirements: when you need full control over your data
• Integration of existing systems: when the software has to be seamlessly integrated into your existing IT landscape
• Competitive advantage: when the software itself is a differentiator from your competitors

Case study: the Adlegio management system

A concrete example of the advantages of custom software is the Adlegio management system, which we developed for our own business processes and for clients. It combines the features that SMEs actually need — without the ballast of an overloaded SaaS solution:

• Customer management (CRM): contacts, companies, communication history — clear and fast
• Quotations and invoicing: create and send professional documents in just a few clicks
• Task and project management: assign tasks, set deadlines, track progress
• Scheduling: integrated calendar with reminders
• Dashboards: revenue, open tasks, invoices due — everything at a glance
• Multilingual: German and English built in from the ground up

The system was developed with Django and is fully tailored to our processes. No unnecessary features, no complicated navigation, no restrictions. And: full GDPR compliance with data stored in Germany.

Technology: why Django is the ideal foundation

Django is a Python-based web framework that is particularly well suited to custom business applications. Its advantages over other technologies:

• Rapid development: Django's "batteries included" philosophy covers an ORM, admin interface, authentication and more — ideal for rapid prototyping and MVP development
• Security: built-in protection against SQL injection, XSS, CSRF and other attacks
• Scalability: from Instagram (billions of users) to an SME tool — Django scales with your requirements
• Python ecosystem: access to data analysis, AI/ML integration, automation
• Longevity: Django has existed since 2005 and is actively developed — a stable, future-proof framework

Conclusion: the right software for your business

SaaS solutions have their place — especially for getting started quickly and for standardised processes. But if your business is growing, has special requirements or wants to optimise costs in the long term, custom software offers more flexibility, more control and lower total costs.

The decision between SaaS and custom is not a question of "good or bad" — it is a question of "fits or doesn't fit". Analyse your actual requirements, calculate the total costs over 3–5 years and make an informed decision.

Our recommendation: If you find that you constantly have to "bend" your SaaS solution, that you are paying for features you don't use, or that licence costs rise year after year — then it is time to think about custom software.

Would you like to know whether custom software makes sense for your business? Contact us for a free initial consultation — we will analyse your requirements and show you the options.