Agency SEO is the outsourced version of a job most businesses cannot staff: making a site the answer a search engine returns for the queries that bring buyers. The work is real, but the market around it is noisy, and the buyer usually cannot tell a disciplined operator from a confident one until the invoices have been running for months. Google publishes its own guidance for this exact purchase, and it is unusually direct about what a good agency looks like and what a bad one sounds like. This page sets out what an agency SEO engagement contains, which questions separate the two, and how to verify an agency's claims against pages it has already published.
What an agency SEO retainer contains
Three layers of work sit inside almost every retainer, and a proposal that quotes only one is quoting part of the job. Technical work makes the site crawlable, fast and correctly structured, which Google's starter guide treats as a foundation rather than a differentiator. Content work builds pages that answer what buyers actually type; Google's own guidance says creating genuinely useful, well written content influences search visibility more than most other factors, and its helpful content guidance asks whether a reader finishes the page able to achieve their goal. Authority work earns links and citations from sources that already carry weight. Ask an agency to show you the split of hours across those three layers for a comparable client. An agency that cannot describe the split is selling an activity report, not a strategy.
What Google's hiring guidance tells you to ask
Google publishes hiring advice for this purchase and it reads like an interview script. Ask for examples of previous work and success stories. Ask whether the agency follows Google Search Essentials. Ask what results they expect and in what timeframe, then compare the answer against Google's own statement that some changes take effect in a few hours while others can take several months. Google also names the warning signs: be wary of firms that email you out of the blue, be careful if a company is secretive or will not clearly explain what it intends to do, and treat claims of a special relationship with Google as a red flag. The line that settles most sales calls is Google's own: no one can guarantee a number one ranking on Google. During an audit, grant read access to Search Console and not write access.
The tactics that can cost you the visibility you paid for
Google's spam policies name the shortcuts that appear inside cheap agency packages. Buying or selling links for ranking purposes is link spam by definition. Scaled content abuse covers generating many pages without adding value, including with generative tools, which matters now that a thousand page build costs an agency almost nothing. Doorway abuse covers sets of near identical pages built to catch specific query variants while funnelling everyone to the same destination, which describes the city page sprawl some agencies sell as local coverage. Keyword stuffing and cloaking round out the list. Google states that sites violating these policies may rank lower in results or not appear in results at all, so the risk lands on your domain rather than the agency's. Ask any candidate to describe its link sourcing and content production in writing before you sign.
How to verify an agency before the first call
Everything worth checking is already published. Does the agency show a real address and a named team, or only a contact form? Does it print prices, or does every scope require a call? Do its case studies name the client and the metric, or do they describe an unnamed client in a large industry? Does the agency itself rank for the specialty phrase it sells, which is the cheapest available proof that its methods work on a site it fully controls? Directories like this one list agencies on what can be verified from their own pages, and the same standard is easy to apply to any shortlist you assemble elsewhere. When two candidates look equal on paper, the one whose published evidence survives an hour of checking is the safer retainer.
Questions people ask about agency seo
Can an SEO agency guarantee first page rankings?
No. Google states plainly that no one can guarantee a number one ranking on Google, and its hiring guidance lists ranking guarantees and claimed special relationships with Google among the warning signs. A credible agency forecasts ranges and reports progress against them.
How long before an agency SEO retainer shows results?
Google's starter guide says some changes might take effect in a few hours while others could take several months, and suggests giving several weeks before judging whether work has moved anything. Ask a candidate for its expected timeframe in writing at proposal stage and hold the reporting to it.
What access should I give an agency during an audit?
Google's guidance is to grant only read access to Search Console at the audit stage, not write access. Full access can come later once the relationship is established and the scope is agreed.
How do I check an agency's claims before I call?
From its own published pages: address, named team, printed prices, case studies that name a client and a metric, and whether the agency ranks for the phrase it sells. That takes about an hour and removes most of a shortlist.