Hiring a senior AI consultant through a Big Four or large agency can cost 3 to 10 times more than working with an independent consultant of equivalent seniority — and not always for the reason you'd expect. A high price tag doesn't guarantee senior execution: in many projects, the person actually doing the work is a junior you'll never meet. Understanding where your budget really goes in each model is the first step to making the right choice.
How much do Big Four firms and large agencies actually charge for AI consulting?
The major consultancies — Accenture, Deloitte, McKinsey, KPMG, PwC, EY, BCG — and national-scale AI agencies bill between €150 and €500+/hour for a senior profile. AI transformation projects start in practice at €50,000–€100,000 and rarely come in lower once you add the diagnosis, design, implementation, and change management phases.
Where does that price come from? Brand, overhead, management layers — and, in many projects, the junior or recently graduated profiles who execute the work while the partner or director only shows up for key presentations.
This doesn't mean large consultancies are bad. For a multinational with hundreds of stakeholders, multiple countries, and six- or seven-figure budgets, that structure makes complete sense: you need large teams, corporate methodologies, and a brand that validates the project internally. That's exactly what they're built for.
Why that model doesn't fit an SME
An SME — whether a firm in Andorra, a fintech, a professional practice, or an e-commerce business — has different needs:
- A defined budget: typically between €5,000 and €30,000 per project.
- Speed: you can't wait six months for a pre-implementation diagnostic.
- Real integration with your existing systems: ERP, CRM, internal databases, current workflows.
- Someone who understands your business, not who adapts a generic framework designed for large corporations.
In that budget range, a Big Four can't assign you a genuinely senior partner for weeks on end. What typically happens is that the initial contact is high-level, but execution ends up in the hands of a junior team managing the project by protocol. The result: over-engineered methodologies, stretched timelines, and systems that rarely survive the first three months after delivery.
What does an independent senior AI consultant charge?
An independent senior AI specialist works with much more straightforward pricing structures:
| Format | Indicative range |
|---|---|
| AI diagnostic | €1,000–€2,000 |
| Fixed-scope project (private ChatGPT, RAG, agents, automation) | €3,000–€10,000 |
| Ongoing collaboration (monthly retainer) | €2,000–€4,000/month |
| Day rate | €800–€1,500/day |
These figures are indicative and vary by complexity, integration depth, and whether the system requires dedicated infrastructure. What doesn't vary: you know exactly who you're working with, what they'll build, and what it will cost before you start.
The real difference: who actually does the work
This is the point most businesses miss when evaluating proposals.
In a Big Four or large agency, the process typically goes like this: a director or partner manages the relationship and presents the project. The actual work is executed by a team of junior consultants — sometimes fresh master's graduates — applying standard methodologies and learning on your project. You never meet that person, and they'll probably change between phases.
With an independent senior consultant like César García Cabeza, the model is different: from the first call to final delivery, you work with the same senior profile who designs the solution, writes the code, configures the systems, and resolves the problems that arise. No intermediate management layer, no analysis team "translating" what the senior said, no scope surprises mid-project.
César García Cabeza combines 5 years as a Data Scientist in digital marketing working alongside CMOs and VPs, experience as Head of R&D in agentic AI, and two master's degrees (AI and Data Science & Cloud Engineering). Through Smart Growth, he builds production-ready systems: private ChatGPT for businesses (Enclave), MCPs over internal APIs, RAG over internal documentation, backoffice automation, and custom AI agents.
"With a large consultancy, the director sells you the project and a junior executes it. Here the end-to-end is with me, César García Cabeza. If the system has a problem three months later, you don't file a support ticket — you call me."
— César García Cabeza, senior AI consultant in Andorra
When does a Big Four actually make sense?
Honesty is part of the deal. A Big Four makes sense when:
- The project requires teams of five or more people working in parallel for months.
- Multiple business areas and hundreds of users are impacted.
- The budget exceeds €100,000 and the expected return clearly justifies it.
- You need the consultancy's brand to validate the decision internally to a board or steering committee.
For those projects, an independent senior consultant is not the right fit. But if you run a business of 10 to 200 people and want an AI system that works in production — without paying for overhead or profiles you'll never see — the equation looks different.
In summary
A Big Four price tag doesn't necessarily buy senior execution: it buys brand, methodology, and coverage for large-scale projects. For an SME, that model is a poor fit and the budget rarely justifies the output. An independent senior consultant brings real judgement, direct contact, and systems that work — at a fraction of the cost and without the risk of ending up working with someone you never meet.
Want to see what makes sense for your specific situation? Talk to César and let's work it out.