Every firm deciding what to do about AI reaches the same fork. There is a tool with a monthly price that promises to do the thing. There is a partner who will build the thing on your own data and rules. The honest answer is that both are right, for different work, and the useful question is which kind of work you are looking at.
Here is the rule we use, and the reasoning behind it.
The rule
Buy when the work is generic, the data lives in one tool, and nobody needs to apply your firm's rules to the output before it is used.
Build when the workflow crosses systems, when the output has to follow rules specific to your firm, when a person has to review every result before it moves, or when nothing exists for your practice area.
Rent the model either way. Nobody builds a model. The decision is about everything around it.
- Meeting transcription and notes
- General drafting help inside a word processor
- Search inside one product you already use
- Translation, summarization, dictation
- A chatbot on your website that answers from your pages
- Intake that qualifies, books and summarizes across phone, email and your CRM
- Documents read onto your forms, with every figure traced to its source
- Chasing and status from one live record per matter or client
- First drafts from your own precedents, following your rules, for a person to edit
- Anything where the product for your practice area does not exist
Why generic work is a buy
A subscription tool wins when the work looks the same in every firm. Transcribing a meeting is the same in a law firm and a dental practice. The tool has seen a million meetings, the vendor maintains it, and your only decision is whether to pay.
These tools help individuals go faster. They do not change how a matter, a client or a report moves through the firm, because they do not know what a matter or a client is. That is fine. Buy them, put them on the one-page list of what is allowed, and move on.
Why cross-system work is a build
The workflows that eat a firm's week are the ones that cross tools. An inquiry arrives by phone, is logged in a CRM, is booked on a calendar, and is summarized for the person taking the call. A document arrives by email, is filed to a matter, is read for its figures, which go onto a form, which a person reviews. Status is answered from a practice management tool, an inbox and someone's memory.
No subscription product sits across all of those, because every firm's combination is different. What a build does is put one live record under the workflow, connect the tools the firm already uses to it, and run the model over that record with the firm's rules. The model is a small part of it. The record, the rules and the review loop are the system.
The rules test
Here is a quick way to tell which side a workflow falls on. Write down what has to be true of the output before someone in your firm would act on it.
If the list is empty, or amounts to "it reads well", buy.
If the list has your firm's rules on it, such as which forms this case type needs, what counts as income for this affidavit, which precedent applies to this client, who has to approve before this goes out, build. A product cannot know those rules. A system built for you can carry them, and show its work against them.
The hybrid most firms end up with
In practice a firm does both. The individual tools are bought and used by whoever wants them. The one or two workflows that define the firm's week are built, with a named owner, one measured number, and a data layer that the next system reuses.
The order matters. Buy the cheap tools now, since they cost nothing to try. Build the first system in the workflow with the clearest before and after, usually intake or chasing. Judge the build by the number, not the demo. Then decide the next one.
What a build should cost you in attention
Two working sessions to agree the workflow, the rules and the number. A couple of hours a week from the owner during the build. A few hours a month afterwards. If a partner asks for more of your time than that in the first ninety days, the scope is wrong.
What to do with this
List the three workflows that eat the most of your week. Run the rules test on each. The ones with an empty list go on the buy pile. The one with the longest list, and the clearest before and after, is the first build.
If you want help deciding, we score a firm across its four areas in four minutes and say which workflows are worth building and in what order.