The verdict in three sentences
A custom approval web app costs between EUR 15,000 and 40,000 excl. VAT in 2026, depending on the number of workflows, integrations and approval levels. E-signature plugs in through an API (Yousign, Docusign) for EUR 0.80 to 2 per signature, and an advanced signature covers 95% of purchase orders and supplier contracts. The real gain is time: a 6-day paper circuit falls to 24 hours, with a timestamped audit trail your auditors will appreciate.
Simple, advanced or qualified: which eIDAS level to choose
The eIDAS regulation (and its eIDAS 2 revision), which applies in Ireland as across the EU, defines three levels. The choice depends on the legal risk of the document, not only its amount.
| eIDAS level | Signer verification | Indicative API cost 2026 | Legal weight | Typical business use |
|---|---|---|---|---|
| Simple | Email + code or click | EUR 0.80 to 1.20 | Admissible, burden of proof on you | Internal purchase orders, expense claims |
| Advanced | SMS code + identity linked to signer | EUR 1.20 to 2 | Strong, practical presumption | Supplier contracts, amendments, signed quotes |
| Qualified | In-person or video ID check + qualified certificate | EUR 4 to 15 | Equivalent to handwritten signature | Leases, sensitive HR documents, public tenders |
| Electronic seal | Certificate in the company's name | EUR 0.30 to 1 per document | Integrity and origin of document | Outgoing invoices, certificates |
| Qualified timestamp | Dated token from a qualified provider | EUR 0.05 to 0.20 | Certain date | Audit trail, evidential archiving |
For 400 purchase orders a month, you usually combine a simple signature for internal approvals and an advanced signature for the final commitment to the supplier. The annual API cost stays around EUR 5,000 to 7,000.
What the app costs, line by line
The signature API only signs. The value lies in the workflow engine: who approves what, from which threshold, with which delegation when someone is away.
| Item | Scope | Budget excl. VAT 2026 (order of magnitude) | Timeline |
|---|---|---|---|
| Scoping and workflow mapping | Workshops with finance, procurement, management | EUR 2,000 to 4,000 | 1 to 2 weeks |
| Workflow engine | 2 or 3-level circuits, amount thresholds, delegations | EUR 5,000 to 12,000 | 3 to 5 weeks |
| Signature integration | Yousign or Docusign API, webhooks, reminders | EUR 2,500 to 5,000 | 1 to 2 weeks |
| ERP or accounting connection | Sage, Xero, Odoo, Business Central | EUR 3,000 to 10,000 | 2 to 4 weeks |
| Audit trail and archiving | Timestamped log, evidential PDF export, 10-year retention | EUR 1,500 to 4,000 | 1 to 2 weeks |
| CFO dashboard | Average delays, bottlenecks, open commitments | EUR 1,000 to 5,000 | 1 to 2 weeks |
| Total | EUR 15,000 to 40,000 | 8 to 14 weeks |
Maintenance then runs at 15 to 20% of the initial budget per year, hosting included. Off-the-shelf tools (Spendesk, DocuWare, Approval Max) cost EUR 20 to 60 per user per month but impose their own circuits: custom work pays off as soon as your thresholds, entities or ERP fall outside the standard.
Design rules that prevent failure
Three mistakes recur in paperless projects. The first is copying the paper circuit as is, with its duplicate sign-offs: use the project to remove one level out of two below EUR 5,000. The second is forgetting delegation, so everything stalls when the CEO is on leave. The third is storing signed PDFs without the provider's evidence log, which weakens their evidential value.
A simple rule works well: automatic approval under EUR 500, one level between EUR 500 and 5,000, two levels above, three levels including the CEO over EUR 50,000.
Mini case study
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Claire, CFO of a 180-employee manufacturing SME in Dublin, approves 400 purchase orders a month. Each order travels between three offices for 6 days on average and takes about 25 minutes of admin time (printing, chasing, scanning, filing).
Calculation: 400 × 25 min = 167 hours per month. At a loaded hourly cost of EUR 38, that is EUR 6,350 per month, or EUR 76,000 a year. After rolling out a EUR 28,000 app with advanced signatures at EUR 1.50 (400 × 1.50 × 12 = EUR 7,200 a year), time falls to 5 minutes per order, i.e. 33 hours a month and EUR 15,200 a year. Net annual gain: 76,000 − 15,200 − 7,200 − 4,500 maintenance = about EUR 49,000. Payback: under 7 months, not counting the early-payment discounts recovered thanks to the 24-hour turnaround.
FAQ
Is a simple e-signature valid for a purchase order?
Yes, it is admissible in court under eIDAS. The burden of proof rests with you, hence the importance of the timestamped audit log, which costs EUR 0.05 to 0.20 per document.
Yousign or Docusign for a European SME?
Yousign is an eIDAS-qualified European provider, with APIs around EUR 1 to 1.50 per advanced signature at volume. Docusign is pricier (often EUR 1.50 to 2) but relevant if most of your suppliers are in the US or UK.
How long to go live?
Allow 8 to 14 weeks for 2 to 3 workflows and one ERP integration. A first pilot circuit can run in 5 weeks.
Do signed documents have to be kept for years?
For accounting records in Ireland, generally 6 years, and many groups align on 10. Evidential archiving on encrypted storage usually costs EUR 20 to 80 a month for a few thousand documents a year.
Can approval be integrated into our existing ERP?
Yes, through APIs or file exports. A Sage or Odoo connection costs EUR 3,000 to 6,000, an SAP connection more like EUR 8,000 to 10,000 depending on available access rights.
Let's scope your project. Send us your current workflows and monthly volume: we will price an app between EUR 15,000 and 40,000 excl. VAT with a 5-week pilot. 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.
