The arithmetic is straightforward. Most management arrangements charge either a percentage of spend or a monthly minimum, and the minimum is what applies at small budgets. A business spending a modest amount monthly and paying a management fee is frequently paying more to manage the campaign than the campaign spends, which means most of the money buys administration rather than customers.
Learn it on a small budget first, which is achievable and considerably more useful than it sounds. The basics are a handful of concepts: match types, negative keywords, the search terms report, and conversion tracking. A few weeks of running something small teaches enough to make an informed decision later, and it means you can tell whether somebody you hire is doing anything.
The threshold worth applying is where the time cost genuinely exceeds the fee. Managing a campaign properly takes a few hours a month, and once your own hours are worth more than that and the spend justifies the percentage, hiring makes sense. That point arrives at different budgets for different businesses.
What you are actually buying is attention rather than access, which is worth being clear about. The platforms are available to anybody, the interfaces are usable, and the knowledge is documented. What a good manager provides is somebody looking at it weekly, catching the wasted spend, and testing systematically, which is precisely the work a busy owner stops doing after month two.
Ask what specifically they will do each month and what result each action is expected to produce, since that question separates people managing an account from people reporting on one. Adding negative keywords, restructuring campaigns, testing landing pages, and adjusting bids are actions. Monitoring performance is not.
Insist on owning the account, which is the single most important condition. An advertising account in your name with them granted access means you keep the history, the data, and the learning if the relationship ends. An account they own means starting again, and that arrangement is common enough to check for explicitly.
Watch the fee structure for the incentive it creates, since a percentage of spend rewards spending more rather than spending well. That is not necessarily a problem and it is worth understanding, and a flat fee removes the tension entirely.
Then judge it on cost per acquired customer rather than on the metrics the platform reports, and give it a fair period before concluding. A manager inheriting an account frequently spends the first month fixing structural problems, and the improvement appears afterward.
Ask to see an account they currently manage, with the client's permission, since that is considerably more informative than a case study. What the campaign structure looks like and whether negative keywords are being maintained tells you within minutes whether the work is real.
Agree what happens to the account if the relationship ends before it starts, including access, history, and any assets built. That conversation is straightforward at the outset and considerably harder once somebody has decided to leave.
Keep conversion tracking in your own hands rather than theirs, since a manager who controls the measurement is reporting on their own performance. Configuring it yourself, or at minimum having full access, is what makes the reporting checkable.
Give it a defined trial with stated expectations rather than an open ended arrangement, since advertising management is easy to continue on inertia and difficult to evaluate without a point at which somebody asks whether it worked.