Match the agency to your gap
If one channel is holding you back, a specialist will go deeper than a generalist. If you need several channels coordinated, full-service fits. Decide where your real bottleneck is before you shortlist, so you're comparing the right kind of agency instead of being talked into scope you don't need. One trap here — an agency that's strong in the channel they want to sell you, not the one you actually need, will still pitch hard. Lead with your problem, not their menu.
Full-service or specialist: how do you tell which you need?
Count the channels that already bring you customers at a cost you can live with.
If the answer is none, start with a specialist, or a freelancer, on the one channel most likely to work, and put the money you save into that channel. A full-service retainer at this stage pays for coordination you don’t have yet. One r/PPC thread shows the mismatch: a new online store paid a boutique agency a $2,000 monthly retainer to run Google and Meta ads on about $1,000 of ad spend. Google was returning 2.5 times the spend after six weeks; Meta wasn’t, partly because the owner had little good creative to give them. A highly upvoted reply said to drop Meta, move the money into Google, and ask for a smaller retainer for one platform (r/PPC, November 2024).
If one channel works and you want to add a second, hire a specialist for the second and leave the first where it is.
Full-service earns its fee once several channels work and the problem sits between them: budgets argued channel by channel, campaigns telling different stories, every channel claiming the same sale. Then one team that owns the plan and the numbers is worth paying for.
Whoever you hire, ask who does each channel, their own staff or subcontractors. A full-service agency that is strong in one channel and outsources the rest is, in practice, a specialist reselling the others. Vendor pitch questions covers how to ask and how to score the answers.
Look past the pitch
The slickest deck and the worst delivery often come from the same agency, because selling and doing are different skills. Ask who will actually run your account day to day and how senior they are — pitches are run by senior partners, accounts frequently by juniors. Ask how they report outcomes, and to see real results for businesses like yours, not logos on a wall. Be wary of guaranteed rankings or lead numbers, vague scopes, and prices far below the rest — they reappear later as disappointment or change orders.
The questions that actually separate them
Most agencies clear the easy questions, so press on the ones that don't fit a script. Who owns the accounts, assets and data if we part ways? What's your reporting cadence, and will you show losses as plainly as wins? What's the notice period and what happens to in-flight work? How do you decide what to stop doing? An agency that answers these crisply has done the work before — vague answers here predict vague work later.
Spot the red flags early
A few signals tend to show up before the trouble does. Guarantees of specific rankings or revenue — nobody controls Google or the market that tightly. Reporting built on vanity metrics like impressions or follower counts instead of leads and revenue. A single named star in the pitch who vanishes after signing. Contracts with long lock-ins and short notice periods. And reluctance to name the people on your account. Any one is a conversation; two or more is a pass.
Run a small test first
You learn more from one month of real work than from any number of meetings. So where you can, start with a paid audit or a contained first project before committing to a long retainer. Watch how they communicate, whether they hit deadlines, and whether the work shows thinking or just activity. A good agency welcomes this; one that pushes hard for a long lock-in up front is telling you something.
Check for AI-search readiness
In 2026, ask whether the agency works on AI-search visibility — being recommended by ChatGPT, Perplexity and Google's AI — or only the classic channels. Many still haven't adapted, and that capability gap widens every quarter as more buying starts with an AI answer instead of a search-results page. An agency that can't explain how it'd make you the answer an AI gives is selling you 2022's playbook.