Almost nobody publishes real numbers for this. Here are honest ranges for a small firm — and an explanation of where the money actually goes.
The scenario, common to consultancies, engineering firms, agencies, and law practices: years of project files — reports, data, drawings, proposals — and a team that wants to ask "find me the past jobs like this one" and get an answer in seconds. The numbers below assume a firm of roughly ten people with a few terabytes of history, and a requirement that no AI vendor ever sees or trains on the data.
| Approach | Year 1 | Years 2–3 (each) | 3-Year Total |
|---|---|---|---|
| Business AI subscriptions (Claude, ChatGPT, Copilot + connectors to your existing storage) | $3–4K | $3–4K | ~$9–12K |
| Private server in a data center (open AI model you own, on a rented machine only you hold keys to) | $15–21K | $1.5–3K | ~$18–27K |
| Your own hardware on-site (same software, on a server in your office or lab) | $26–36K | ~$1K | ~$28–38K |
The subscription route is by far the cheapest — but it searches your files as they are. It won't build a structured database of every project, won't read twenty-year-old proprietary formats, and the answers are only as good as what a general-purpose tool can find on the fly. For plenty of firms, that's genuinely enough. The two build options exist for firms whose archive — or whose privacy requirements — demand more.
People assume the cost is the AI. It isn't — open models are free, and the software around them is largely off-the-shelf. The build cost is almost entirely labor, and the labor is almost entirely about your files:
A build looks expensive next to a subscription until you run it over time: the year-one cost is high, but years two onward run on electricity and small hosting fees. Firms comparing a ~$25K build against ~$10K/year of software subscriptions break even in about two and a half years — and everything after that is nearly free. For a firm that's been operating for twenty years and plans to operate twenty more, that math tends to settle the debate.
The counterpoint is honest too: subscriptions include someone else maintaining everything. A build is yours — including the upkeep. Factor in who's going to own it before the price difference decides for you.
Book a free assessment. We'll look at what you actually have and tell you which of these paths fits — including the cheap one, if that's the truth.