The verdict in three sentences
At EUR 8 per user per month, an expense SaaS costs a 400-employee company EUR 38,400 a year, over EUR 190,000 across five years. A custom app is built for EUR 30,000 to 45,000 excl. VAT, then about EUR 4,000 a year, with receipt OCR, Germany-Poland-France rules and direct accounting export. Delivered in 10 weeks, it pays back in just over a year and finally fits cross-border project work.
Why SaaS struggles with cross-border projects
Berlin-based engineering, construction and industrial service firms send teams every week to Poland, Czechia, France and the Benelux. Their expense claims mix German MwSt, foreign VAT, per diems under the German Federal Travel Expenses Act rates, accommodation lump sums and recharging by project.
Market SaaS tools handle the standard case of a salesperson travelling domestically well. They handle poorly the allocation by project and client, foreign VAT recovery, posted-worker meal allowances and approvals by site managers. Typical result: 20 to 30% of claims reworked by hand in accounting.
| Criterion | Expense SaaS (EUR 8/user/month) | Custom app |
|---|---|---|
| Upfront cost | EUR 0 - 3,000 (setup) | EUR 30,000 - 45,000 excl. VAT |
| Annual cost (400 employees) | EUR 38,400 | EUR 4,000 (hosting, maintenance) |
| 5-year total | EUR 192,000 - 195,000 | EUR 46,000 - 61,000 |
| Allocation by project and client | Free text, no control | Project list synced with the ERP |
| Foreign VAT (PL, CZ, FR) | Partial | Automatic split for recovery |
| Per diems and country rates | Limited configuration | Rules coded per country |
| Approval workflow | 1 to 2 levels | Site manager, project lead, CFO |
| Accounting export | Generic file | Entries ready for DATEV, SAP or Sage |
SaaS remains the right call under 50 users or for a process with no specifics. At 400 users with strong business rules, the per-seat cost becomes the biggest budget line.
What the EUR 30,000 to 45,000 app includes
| Module | Function | Indicative 2026 budget (EUR excl. VAT) |
|---|---|---|
| Mobile capture and OCR | Photo of the receipt, reads amount, date, VAT | 6,000 - 9,000 |
| Spending rules | Caps, mileage rates, per diems, currencies | 5,000 - 8,000 |
| Cost allocation | Projects, clients, cost centres synced | 4,000 - 6,000 |
| Approval workflow | Multi-level, delegation, reminders | 4,000 - 6,500 |
| Accounting and payroll export | DATEV entries, payroll reimbursement, SEPA file | 5,000 - 8,000 |
| Compliant archiving | GoBD-compliant storage of scanned receipts, timestamps | 3,000 - 4,500 |
| CFO dashboard | Spend by project, approval times, anomalies | 3,000 - 3,500 |
Archiving must meet the GoBD rules on digitised records (replacing scanning, ersetzendes Scannen) before paper originals can be destroyed. Validate this with your tax adviser at the scoping stage.
10-week plan
| Phase | Weeks | Deliverable |
|---|---|---|
| Scoping rules and agreements | 1 - 2 | Rate matrix, workflows approved by the CFO |
| Mobile and back-office mockups | 3 | Prototype tested by 5 field employees |
| Build capture, OCR, rules | 4 - 6 | Test version |
| Approvals, accounting export, archiving | 7 - 8 | Full version |
| Pilot on two projects | 9 | Fixes on real cases |
| Roll-out to 400 employees | 10 | SaaS switch-off, history import |
Plan the end of the SaaS contract into the schedule: most annual contracts require 1 to 3 months' notice.
Mini case study
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Katrin, CFO of a 400-employee industrial services firm in Berlin, pays EUR 38,400 a year for SaaS. Her accounting team reworks 25% of 1,800 monthly claims at 6 minutes each: 45 hours a month, about 540 hours a year and EUR 19,000 of loaded staff time.
The custom app, billed EUR 40,000 excl. VAT then EUR 4,000 a year, removes the licence and brings rework down to 5%. First-year saving: 38,400 + 15,200 - 4,000 = EUR 49,600, for a EUR 40,000 investment. The project pays back in under 10 months, and each following year saves about EUR 50,000.
FAQ
How much does a custom expense app cost in Berlin in 2026?
Order of magnitude: EUR 30,000 to 45,000 excl. VAT for 400 users, depending on business rules and integrations. Hosting and maintenance then cost about EUR 4,000 a year.
From how many users does custom pay off?
Against a SaaS at EUR 8 a month, the break-even sits around 150 to 200 users over five years. Below that, SaaS is usually cheaper unless business rules are very specific.
Does the OCR read Polish and French receipts?
Yes, recognition covers German, Polish, French and the main currencies. Correct reading of amount and date exceeds 90% on standard till receipts, and employees fix the rest in one tap.
Can we destroy paper receipts?
Yes, if archiving follows GoBD replacing-scan requirements: faithful copy, timestamping, 10-year retention for accounting records. This module accounts for EUR 3,000 to 4,500 of the budget.
How does the exit from our current SaaS work?
We import the history from the vendor's exports, usually 2 to 3 years of claims. The switch is timed to the contract end date so you never pay for two tools for more than a month.
Let's scope your project. Tell us your headcount, current tool and accounting software for a quote between EUR 30,000 and 45,000 excl. VAT and a 10-week switch-over plan. 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.