The verdict in three sentences
For an Amsterdam company managing more than 500 recurring contracts, a custom subscription management app at EUR 30,000 to 65,000 pays for itself in 18 to 30 months against manual work. Stripe Billing (0.7% of billed volume) and SEPA Direct Debit handle the payment side, while the app carries your business rules: indexation, proration, multi-site contracts. With France requiring e-invoice reception since 1 September 2026 and the EU's ViDA package pushing structured e-invoicing toward 2030, building UBL and Peppol-ready billing now avoids a second rebuild.
The hidden cost of manual invoicing
Take an industrial equipment maintenance company in the Amsterdam area: 1,400 annual contracts, monthly or quarterly instalments, an indexed price review every January. Everything runs on a spreadsheet and a basic invoicing tool.
| Task | Manual (per year) | Custom app (per year) |
|---|---|---|
| Issuing recurring invoices | 230 h | 10 h of checks |
| Annual price indexation | 60 h | 2 h |
| Payment reminders | 180 h | 30 h (automated dunning) |
| Bank reconciliation | 120 h | 15 h |
| Average days sales outstanding (DSO) | 52 days | 28 days with SEPA |
| Invoice error rate | 3 to 5% | < 0.5% |
At a loaded cost of EUR 35 per hour, the 590 manual hours represent about EUR 20,650 a year. Lower DSO also frees cash: on EUR 2.8M of recurring revenue, going from 52 to 28 days frees about EUR 184,000 of working capital.
Custom build, Chargebee or off-the-shelf: the comparison
Custom is not always the right answer. Here are the realistic 2026 options for 1,400 contracts and about EUR 2.8M billed per year.
| Option | Initial cost | Annual recurring cost | Strengths | Limits |
|---|---|---|---|---|
| SME invoicing software (Moneybird, Exact Online) | EUR 0 to 3,000 | EUR 1,500 to 6,000 | Fast, e-invoice ready | Limited indexation and multi-site rules |
| Chargebee or Recurly | EUR 5,000 to 15,000 (integration) | EUR 8,000 to 25,000 (plan + % of volume) | Mature subscription logic | Cost rises with volume, poor fit for maintenance contracts |
| Custom app + Stripe Billing | EUR 30,000 to 65,000 | EUR 19,600 (0.7% of 2.8M) + EUR 4,000 to 8,000 maintenance | Your exact rules, client portal | Upfront budget, 3 to 5 months |
| Custom app + direct SEPA (via bank) | EUR 35,000 to 70,000 | EUR 3,000 to 6,000 + maintenance | Minimal transaction fees | Mandate and return handling to build |
The sensible split: under 300 simple contracts, off-the-shelf software is enough. Above 800 contracts with indexation, proration and multi-site invoicing, custom wins. A hybrid model is common: custom app for contract logic, Stripe for collection, a certified access point for Peppol e-invoice delivery.
Scope, budget and typical schedule
| Module | Indicative budget | Duration |
|---|---|---|
| Clients, contracts and sites database | EUR 6,000 to 12,000 | 3 to 4 weeks |
| Recurring billing engine (proration, CPI indexation) | EUR 8,000 to 16,000 | 4 to 6 weeks |
| Stripe Billing and SEPA mandates integration | EUR 5,000 to 10,000 | 2 to 3 weeks |
| E-invoicing connector (UBL, Peppol access point) | EUR 4,000 to 9,000 | 2 to 3 weeks |
| Client portal (invoices, payment methods, contracts) | EUR 4,000 to 10,000 | 2 to 4 weeks |
| MRR, churn and DSO dashboards | EUR 3,000 to 8,000 | 2 weeks |
| Total | EUR 30,000 to 65,000 | 3 to 5 months |
Mini case study
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Sarah, CFO of an industrial maintenance company in Amsterdam, manages 1,400 contracts for EUR 2.8M billed per year. She approves a EUR 48,000 project, with Stripe Billing (EUR 19,600 per year) and EUR 6,000 of annual maintenance. Annual gains: EUR 17,300 of admin time saved (495 hours at EUR 35), EUR 9,000 of bad debt and errors avoided, and EUR 184,000 of cash freed once. In running costs the net annual gain is modest (about EUR 700), but the freed cash funds the project four times over in the first year.
FAQ
Is e-invoicing mandatory for a Dutch SME in 2026?
Not yet for domestic B2B in the Netherlands, but France requires e-invoice reception from 1 September 2026 and the EU ViDA package targets structured e-invoicing for cross-border B2B by 2030. If you invoice French clients, UBL or Peppol output is already a practical requirement.
How much does Stripe Billing cost?
On the standard plan, Stripe Billing charges 0.7% of billed volume, on top of payment fees (about EUR 0.35 per SEPA debit in the eurozone). For EUR 2.8M billed, expect close to EUR 19,600 per year excluding transaction fees.
Can we keep our current accounting software?
Yes. The app exports entries to your accounting tool (Exact Online, Twinfield, AFAS) via API. This connector usually costs EUR 2,000 to 5,000.
How long does it take to migrate 1,400 existing contracts?
Plan 2 to 3 weeks of data migration, with a controlled import and a dry-run billing cycle. Expect 5 to 10% of contracts to need corrections.
Do we need a custom build or is Chargebee enough?
Chargebee fits standardized SaaS subscriptions. For maintenance contracts with indexation, multiple sites and amendments, custom avoids 20 to 30% of manual workarounds.
Let's scope your project. Share your contract count, billing rules and accounting tool: we propose a scope, a budget between EUR 30,000 and 65,000 and an e-invoicing-ready schedule. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
