Build costs, by scope
| Scope | Build | Timeline |
|---|---|---|
| Point automation | €3,000–8,000 | 2–4 weeks |
| Complete process for one department | €5,000–15,000 | 4–8 weeks |
| Several integrated processes with agents | €10,000–35,000 | 8–16 weeks |
| Multi-department system with orchestration | €25,000–120,000 | 12–24 weeks |
Running costs sit between €300 and €2,500 a month depending on usage. On the wider market, prices go from around €2,000 for a basic chatbot to €500,000 for enterprise projects.
Some reference cases we publish
- A customer service agent for a B2B mid-market company: €8,000–25,000 depending on integrations, plus €800–2,500 a month to run.
- A WhatsApp Business agent: €8,000–18,000 depending on the use case, plus €300–900 a month. In Spain, each WhatsApp conversation costs between €0.022 and €0.070.
- Departmental automations: €8,000–28,000 each, €600–1,500 a month, 6–12 weeks.
- A swarm of agents across the operation: €80,000–160,000, with €3,500–6,000 a month to run.
- A first 90-day project: €11,000–24,000 in total — analysis €2,500–5,000, first use case €8,000–18,000, operation €500–1,000 a month.
Chatbot or agent: why the price gap
A chatbot costs €500–5,000 and answers static questions; it is still the right choice with a very limited budget (under €3,000) and a stable FAQ. An agent costs €3,000–120,000 because it acts inside your systems: it reads the order, checks stock, decides with your margins, writes to the ERP and escalates what it can't solve. It is common to find companies that have paid €5,000–15,000 for "agents" that are chatbots. If someone offers you an AI agent for WhatsApp at €200 a month with no implementation, it's a menu chatbot.
The cost nobody quotes: supervision
An agent nobody supervises degrades within six to nine months. Prices change, products change, policies change, and exceptions pile up without anyone noticing. That is why the monthly figure matters as much as the build, and why an agent needs someone inside your company who owns it.
Before you pay for an audit
A boutique AI audit (4–8 working days) runs €2,500–5,000; a mid-market one (2–3 weeks) €8,000–15,000; an enterprise one (1–2 months) €25,000–80,000. If you pay less than €1,500 for an AI audit, you get a processed questionnaire, not a diagnosis. More on how we work in AI consulting in Barcelona.
How we start
Always the same way. Day zero: an NDA signed before you show us anything. Then the Nexus team analyses your operation and delivers a report with the exact changes, prioritised by impact on your P&L. Then you decide. Nexus Elite AI is an engineering boutique in Barcelona: two people, no juniors, no subcontractors, and never more than seven clients at a time. Apply and we reply within 24 business hours; if there is no fit, we tell you in writing.
Frequently asked questions
How much does an AI agent cost per month to run?
Between €300 and €2,500 a month depending on usage for most projects we publish ranges for; a customer service agent for a mid-market B2B company runs €800–2,500 a month, and a swarm of agents €3,500–6,000.
Why does an AI agent cost more than a chatbot?
Because it acts inside your systems — ERP, CRM, email, warehouse — and decides with your criteria, which requires integration, testing and supervision. A chatbot only answers questions, which is why it costs €500–5,000.
What is the cheapest sensible way to start?
A single point automation on the process that costs you most, for €3,000–8,000 in two to four weeks, measured against a baseline taken before starting. If it works, the next one; if it doesn't, you know why.
Will an AI agent pay for itself?
We don't promise returns before seeing your data. What we do is take a baseline before starting and measure against it, so the answer comes from your numbers, not from a sales deck.