Hire a custom LLM & RAG development agency

An LLM and RAG development agency builds applications that reason over your own data — most commonly retrieval-augmented generation (RAG), sometimes with fine-tuning. Cost depends on data volume, accuracy needs and integration; on NorthBridge AI you can compare vetted specialists and pay by milestone.

What it is

Retrieval-augmented generation (RAG) connects a language model to your documents so it answers from your knowledge, not just its training data. Fine-tuning adjusts a model's behaviour on your data. Most business use cases are best served by RAG, sometimes with light fine-tuning.

Common use cases

  • Question-answering over internal documents and policies
  • Knowledge assistants for support, sales or research
  • Document analysis, extraction and summarisation
  • Domain-specific copilots for your team
  • Search that understands meaning, not just keywords

What to look for in an agency

  • A clear, evidenced view of RAG vs fine-tuning for your case
  • A rigorous approach to evaluation and accuracy
  • Sensible handling of data, retrieval quality and hallucination risk
  • Awareness of ongoing usage and maintenance costs

Hiring safely and what it costs

Whatever you build, the safeguards are the same: vet the agency, agree a Statement of Work, and pay via escrow-protected milestones. For budgeting, see How much does a custom LLM or RAG app cost. To evaluate candidates, start with How to vet an AI agency and Who owns the IP and code.

Find a verified llm & rag apps agency

NorthBridge AI connects you with vetted agencies for llm & rag apps, each verified before listing, with a signed Statement of Work and escrow-protected milestones on every project. See how it works.

Frequently asked questions

Should I use RAG or fine-tuning?

For most business use cases, RAG is the better starting point — it connects an existing model to your data at query time, which is cheaper to build and easier to keep current than fine-tuning. Fine-tuning adds value when you need consistent style, format or domain behaviour that RAG alone can't deliver. Training a model from scratch is rarely necessary.

How much does a custom LLM or RAG app cost?

A RAG application over your own data commonly costs in the tens of thousands to build, plus ongoing usage and hosting. Fine-tuning adds cost above that. The main drivers are data volume and quality, accuracy requirements, and how deeply the app integrates with your systems.

Hire a verified llm & rag apps agency

Compare vetted agencies and hire with escrow protection on NorthBridge AI.

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