The situation this suits is recognisable. A business with somebody capable of doing the work, or with a preference for doing it themselves, that needs to know what the work should be. Building the thing is frequently the easier half, and deciding what to build is where the expensive mistakes are made.
It also suits a business with a small budget considerably better than a small project does. Advice costs a fraction of implementation and it addresses the decision that determines whether the implementation would have been correct. A business spending its available money on the wrong build has spent it, and the same money spent establishing the right direction leaves the build affordable later.
What that engagement produces is a document rather than a deliverable. What the actual problem is, what to do about it, in what sequence, with the reasoning attached so you can adapt when circumstances change. That last part matters, because a list of recommendations without reasoning stops being useful the moment something differs from what was assumed.
Bring the same information you would for any engagement, since the diagnosis depends on it. What you sell, who buys it, what you charge, where work has come from, and access to whatever exists. Advice given without those is generic, and generic advice is available free.
Expect it to be shorter than an implementation engagement and more demanding of your attention. A few conversations, some analysis, and a written output. The concentrated part is entirely at your end afterward, since you are the one acting on it.
Be honest about whether you will act on it, which is the question worth asking yourself before commissioning anything. A business that receives a clear plan and does none of it has paid for a document, and that outcome is common enough to be worth naming. Advice is only worth what the action produces.
Consider a review of what you have already built as a version of this, which is frequently the most useful few hours available. Somebody looking at an existing site, an advertising account, or a set of tools and telling you what is wrong and what to prioritise costs very little and prevents months of effort in the wrong direction.
Ask what happens afterward, since some providers offer advice as a route into implementation and price it accordingly. A genuinely standalone engagement should be complete in itself, with no obligation and no assumption that you continue, and the output should be usable by anybody you choose to hire.
Come with the specific question rather than a general request, since advice is only as useful as the problem it addresses. A business asking what it should do generally receives a general answer, and one describing a decision it is facing receives something it can act on.
Take notes yourself as well as receiving the written output, since the reasoning discussed in conversation frequently contains more than the summary captures.
Set a date to review what you did with it, since advice not acted on within a few months is usually advice that will not be. That check is what converts a document into a decision.
Ask for the reasoning alongside the recommendation, since circumstances change and a conclusion without its logic stops being useful the moment something differs from what was assumed.