A search advertising agency manages the money you spend to appear when someone types a query describing what you sell. It is the most measurable channel most businesses buy, which is exactly why it produces the most misleading reporting: everything is countable, so a weak agency can always find something that went up. The work itself is unglamorous and largely invisible from outside, which makes the buying decision hard. This page describes what the job actually consists of month to month, how the common fee models shape behaviour, the specific evidence that distinguishes a competent operator from an account left on autopilot, and the terms that protect you when the relationship ends.
What the work actually is, month to month
Setting up a paid search account is a few days of work. Managing one is a different job, and it is where the fee should be earned. The recurring work is query mining and negative keyword maintenance so you stop paying for searches that will never buy, budget reallocation across campaigns as performance shifts, ad and landing page testing with enough volume behind it to mean something, monitoring of automated bidding so the machine is optimising toward a signal that reflects value rather than count, and watching for the failures that quietly waste money: broken tracking, disapproved assets, a landing page that started returning an error, a competitor bidding on your brand. It also includes the unfashionable part, telling you when to spend less. An account that receives none of this still produces a report every month, which is why so many buyers do not notice for a year. Ask a candidate what they would do in the first thirty days, the next sixty, and every month after that, and listen for whether the third answer is as concrete as the first.
Fee models and the behaviour each one produces
Three structures dominate and each creates a pull worth naming out loud. A percentage of ad spend is simple and common, and it rewards larger budgets rather than better ones, which makes a recommendation to cut wasted spend costly for the agency to give. A flat retainer decouples the fee from spend, which is cleaner, but invites scope disputes as the account grows and offers no reward for efficiency won. Hourly billing is the most transparent and the least popular, because it reveals how few hours a large retainer sometimes buys. Performance-based fees sound aligned and need the most care, since paying per conversion optimises for whatever is easiest to count: define the conversion loosely and you will receive a great many cheap, unqualified ones. There is no clean answer, only an informed one. Ask each candidate which model they propose and what conflict it creates, and treat a candid answer as evidence of the judgement you are actually hiring.
The evidence to demand before you hand over an account
Ask for four things. A redacted account structure from a comparable client, so you can see how they organise campaigns and budgets rather than hear it described. The named team with titles and expected hours per month on your account, plus what happens if the lead leaves. A written explanation of how conversion values reach the ad platform, because bidding toward a count rather than toward value is the most common structural weakness in a mid-sized account. And an example of a test that failed and what changed as a result, which is the most revealing question you can ask, because anyone managing real accounts has lost tests. Check also how they will report: brand and non-brand separated, cost per qualified enquiry rather than cost per click, and a plain statement of what changed this month and why. The Federal Trade Commission's guidance on making effective disclosures in digital advertising is worth reading alongside this if your ads carry claims, conditions or pricing, since the disclosure obligations sit with you rather than with the agency.
Ownership, exit terms and comparing candidates fairly
The most expensive mistake in paid search is letting the agency own the account. Create the ad accounts, the analytics property and the tag manager container in your own name and grant the agency user access, so that conversion history, audience lists and bid strategy learning stay with you. Agree the notice period and what happens on exit: access transferred, a documented handover of campaign structure, and no dispute over data. Then compare candidates on like terms by asking each for the disclosed minimum engagement, the fee model with the conflict named, the named team with hours, and what is subcontracted. Buyers frequently reach this decision while comparing search specialists against broader advertising companies that also handle display, social and creative, and the honest test is whether search is the dominant part of your economics or one channel among several. If it dominates, buy depth. If it does not, buy coordination, but insist on seeing the search work priced separately either way.
Questions people ask about search advertising agency
How much does a search advertising agency charge?
Fees are usually a percentage of ad spend, a flat retainer or an hourly rate, and each varies widely by account complexity. The comparable figure is the disclosed minimum engagement, which most agencies will state in writing if asked. Also ask what the fee covers at that minimum, because landing pages, creative, feed management and analytics work are frequently excluded and then billed as extras.
Should the agency use our ad account or their own?
Yours, without exception. Ownership of the ad account keeps conversion history, audience lists and algorithmic learning with you when the relationship ends. Agency-owned accounts create a switching cost that is invisible at signing and painful later, and they also make an independent audit of what actually happened in your account much harder to obtain.
How do I tell if an account is being actively managed?
Ask for the change history from the platform itself rather than a summary, and look at whether changes are substantive or cosmetic. Ask what the last three negative keyword additions were and why, what the current test is, and which campaign had budget moved away from it this month. Specific answers to those questions cannot be improvised by someone who has not been in the account.
Is automated bidding a reason to pay an agency less?
No, though it changes where the value sits. Automation handles bid setting; it does not choose what you count as a conversion, feed value back from your CRM, write the offer, fix a broken landing page or notice that a campaign is buying irrelevant queries. Judge an agency on those decisions, and be sceptical of anyone whose monthly work is mostly adjusting things the platform now adjusts itself.