“I already pay €20 a month for AI – isn’t that enough?”
That’s the phrase we hear most often in professional offices. And it’s entirely understandable: ChatGPT Plus at €20/month works well, and nobody wants to hear about more complicated solutions. Except this question hides another, far more important one: €20 a month to do what, exactly?
Because depending on what you expect from your AI – answering general questions, or working with your own client documents – what you get is radically different. And so is what you’re exposed to.
What you get with a standard subscription
ChatGPT Plus is a general-purpose assistant. It has broad knowledge of law, accounting, and taxation. It can draft letters, summarise texts, and explain complex concepts. That’s already very useful.
But it doesn’t know your practice. It doesn’t know that your client Dupont signed an addendum last March. It doesn’t remember yesterday’s conversation. And every time you start a new session, you begin from scratch.
A standard subscription is an excellent general assistant – not a colleague who knows your files.
There’s also a practical constraint that’s often overlooked: usage limits. ChatGPT Plus allows around 40 messages every 3 hours with the most powerful model. Beyond that, the tool automatically switches to a less capable version. On a busy working day, this limit arrives sooner than you’d expect.
So why are there plans at €30, €60, and beyond?
As soon as you want to integrate your own documents – contracts, client files, internal templates – you enter a different category of service. And that category comes at a price.
Microsoft 365 Copilot (€30/user/month) integrates with your Office suite and can access your SharePoint or Teams files. It’s powerful, but your data remains on Microsoft’s servers – with the legal risks that entails for professionals bound by confidentiality.
ChatGPT Enterprise (around €60/user/month, annual contract) allows you to create workspaces with persistent memory and document bases. It’s OpenAI’s “premium” enterprise solution. But even here, your data goes to servers you don’t control.
In both cases, the promise is the same: an AI that knows your working environment. But at what cost – and under what conditions?
| ChatGPT Plus | Copilot 365 | ChatGPT Entr. | ArkeoAI | |
| Monthly price | €20/user | €30/user | ~€60/user | €0 (fixed) |
| Personal documents | Limited | Yes (cloud) | Yes (cloud) | Yes (local) |
| Memory between sessions | No | Partial | Yes | Yes |
| Message limits | ~40/3h | Yes | Yes | None |
| Data in Europe | ✗ | Partial | ✗ | ✓ |
| GDPR compliance | ✗ | Complex | Possible | ✓ |
| Data stays with you | ✗ | ✗ | ✗ | ✓ |
Indicative prices for 2026. Enterprise plans are on a custom quote with annual commitment.
The real question: where does your data go?
For a lawyer, notary, doctor, or accountant, this question is not trivial. It is legally fundamental.
Every document sent to an American cloud service passes through servers subject to the Cloud Act – a US law that allows authorities to access that data on request, even when hosted in Europe. The CNIL has repeatedly warned that using these services with data covered by professional secrecy exposes practitioners to real risks.
This is not a theoretical question. It is a matter of professional liability – and potentially, disciplinary sanctions.
Beyond the legal framework, it’s also a question of the trust your clients place in you when they share their most sensitive information.
The alternative: an AI that stays in your office
ArkeoAI works on a different principle: the AI is physically installed on your premises, on a dedicated mini PC. It sends nothing outside. No monthly per-user subscription. No message limits.
Your documents are indexed locally, once, at installation. They remain where they should be: with you. And the AI can access them at any time, without an internet connection, without delay, and without additional cost.
For a three-person firm each paying €30/month for Copilot, the annual bill reaches €1,080. With ArkeoAI, that investment pays off in one to two years – and after that, the marginal cost of every question is zero.
What to remember
€20/month for a general AI is a good starting point. But if you want an AI that knows your files, respects professional secrecy and doesn’t generate growing recurring costs, you need to go further.
The right question isn’t “how much does it cost per month?” It’s: “who has access to my data – and am I prepared to take responsibility for that?”
