A PPC agency runs paid search and paid social on your behalf: building campaigns, setting bids, writing ads and landing pages, and reporting on what the spend returned. Unlike search work, the results arrive within days, which is why the market is crowded and why weak operators survive in it. The money moves whether or not the account is well managed, and a report can look busy while the account quietly wastes budget. The useful defence is that Google documents how its auction works, so the mechanics a good agency manages are public. This page covers how agencies charge, what the auction actually rewards, and the questions that tell an operator from a reseller.
What the auction actually rewards
Google's documentation defines Ad Rank as a set of values used to determine whether your ads are eligible to show and, if eligible, where on the page they are shown. It names six components: your bid, the quality of your ads and landing page, Ad Rank thresholds, the competitiveness of the auction, the context of the search including location, device, time and search terms, and the expected impact from your ad assets and other ad formats. Google's own statement is that higher quality ads can often lead to lower CPCs, meaning you pay less per click when your ads are higher quality. That is the whole case for hiring a competent agency in one sentence: quality is a lever on cost, not just on volume, and it is the lever an agency actually controls.
Quality Score, and what it is not
Quality Score is the number most agencies put on a slide, and Google is explicit about its status: Quality Score is not an input in the ad auction; it is a diagnostic tool to identify how ads that show for certain keywords affect the user experience. That matters when you read a proposal. An agency that promises to raise Quality Score as the deliverable has confused the dashboard with the account. The right use is diagnostic: a low score points at a mismatch between the query, the ad and the landing page, and fixing that mismatch is what moves cost per click, because ad and landing page quality is a genuine Ad Rank component. Ask a prospective agency to explain the distinction. The answer sorts the field quickly.
How PPC agencies charge, and what each model rewards
Three models dominate. A percentage of ad spend is simple and scales with the account, but it pays the agency more when you spend more, which is a poor incentive if efficiency is the goal. A flat monthly management fee decouples the fee from the budget and rewards discipline, but can leave a large account under-serviced. Performance-based pricing pays on outcomes and sounds ideal, but only works when conversions are tracked cleanly and attributed honestly, which is exactly the thing under dispute when performance is poor. Many agencies mix them, typically a base fee plus a smaller percentage. Ask which model applies at your budget, what the fee does when spend halves, and who owns the account if you leave.
Ownership, access and the exit test
The single most expensive mistake in paid media is running spend through an account you do not own. Insist that the ad accounts, the conversion tracking, the analytics property and any tag management container sit in your name, with the agency granted access rather than holding title. That way leaving is a permissions change rather than a rebuild, and you keep the account history that bidding systems rely on. Ask, before signing, exactly what you would take with you: campaign structure, negative keyword lists, audience definitions, creative assets and the conversion data. If the answer is vague, that vagueness is the switching cost, and it will be priced into every renewal conversation you ever have with that supplier.
The questions that separate operators from resellers
Ask who will actually work on the account, by name, and how many accounts that person carries. Ask what they would change in the first thirty days and why, which forces a specific answer about your account rather than a generic method. Ask how search terms are reviewed and how often negatives are added, since that is the routine work that stops budget leaking. Ask for a report you can read against the platform interface, not a rebuilt dashboard that only they can reconcile. And apply Google's general hiring guidance, which warns against firms that email out of the blue, against claimed special relationships with Google, and against anyone unwilling to explain their methods clearly. Those warnings were written about search, and they read just as well for paid.
Questions people ask about ppc agencies
How much do PPC agencies charge?
Common models are a percentage of ad spend, a flat monthly management fee, or a base fee plus a smaller percentage. Ask which model applies at your budget, what happens to the fee if spend halves, and whether the incentive it creates matches the efficiency you want.
Does a higher Quality Score guarantee cheaper clicks?
Quality Score itself is a diagnostic, and Google states it is not an input in the ad auction. What is an input is the quality of your ads and landing page, one of the six Ad Rank components, and Google says higher quality ads can often lead to lower CPCs.
Who should own the Google Ads account, me or the agency?
You should. Keep the ad account, conversion tracking, analytics and tag container in your own name and grant the agency access. That makes a change of supplier a permissions change rather than a rebuild, and preserves the account history that bidding relies on.
Can a PPC agency guarantee a cost per lead?
Not credibly. Cost per click depends on your bid, ad and landing page quality, auction competitiveness and search context, and competitors change their behaviour constantly. Ask for a forecast with stated assumptions and a plan for what changes if the assumptions break.
How do I judge a PPC agency in the first month?
Look at search term reviews and negative keyword additions, conversion tracking that reconciles with your own records, and a written account of what changed and why. Reporting you cannot reconcile against the platform interface is the first warning sign worth acting on.