The three options are optimised for different things, and most of the disappointment I hear about in scoping calls comes from picking one that was built for a different job than the one at hand.
What each is actually built for
Agencies
An agency is built to run several projects at once with a repeatable process: account manager, project manager, designer, developer. That structure is well suited to larger projects with multiple stakeholders who need formal reporting, and it comes with the overhead of handoffs between roles, which shows up in both cost and speed.
Freelancers
A freelancer is usually one person handling a narrower piece of work, often on an hourly or day rate, and often juggling several clients in parallel. That is well suited to a defined task with a clear brief, and less well suited to open-ended scoping where requirements need to be worked out as you go.
Independent consultants
An independent consultant handling a project end to end, from scoping through build to support, sits between the two: one point of contact, no handoff between roles, and usually a fixed price agreed after the scope is understood rather than a running hourly meter.
Questions that reveal the right fit
- How many stakeholders need to sign off on decisions along the way, since more stakeholders usually favours the more formal process an agency provides
- Whether the requirements are fully defined already, or need to be worked out through the process itself
- Whether ongoing ownership after launch matters to you, and who will actually hold that relationship
- How much the project depends on one person understanding the whole system, versus being split across specialists
The question is rarely which option is best. It is which one the project actually needs.
— On structure, not quality
Where this leads
None of the three is a strictly better choice than the others. A systems review is a useful first step regardless of which structure you choose afterwards, because it separates the scoping question from the vendor question.