Plain English · 1 min
Off-the-shelf vs fitted vs fine-tuned: which do you need?
Three very different price tags hide behind the word 'AI'. Here's the honest sorting, including the one you almost certainly don't need.
Plain English · Updated 24 September 2026
The three tiers
Off-the-shelf
ChatGPT, Claude and friends, subscribed to and used by hand. Brilliant for personal, one-off work — drafts, ideas, summaries. Limits: it knows nothing about your business, runs only when you're driving it, and answers only you, not your customers.
Fitted
A general model connected to YOUR information and systems — grounded in your prices, plugged into your bookings, running around the clock with approval steps. No new model is trained; the intelligence is rented, the fit is built. This is what most businesses actually mean when they wish 'AI' would help, and it's what a Build is.
Fine-tuned
An actual custom-trained model. Genuinely needed only in rare cases — highly specialised language, massive volume, unusual constraints. If a vendor leads with fine-tuning for a small business, ask precisely what the fitted tier fails at first. Usually nothing.
The honest sorting rule
If your need is occasional and personal, stick with off-the-shelf options. Save your money. For recurring and customer-facing tasks, consider bespoke solutions. Reliability and consistency matter here. Fine-tuning is key when someone can clearly show why customisation is essential. For example, a consultant drafting a proposal now and then might need tier one. A clinic answering booking questions all day would need tier two. Almost nobody reading this needs tier three. We'd tell you if you did, as we sell the middle option and would rather you buy nothing than the wrong one.
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Describe what you'd want AI to do and I'll sort it into a tier honestly — including 'just use ChatGPT' when that's the true answer.
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