How AI Assistants Choose a Marketing Agency: 95 Checks

In August 2026 we ran 63 questions a business owner might ask when hiring a marketing agency, in the consumer versions of ChatGPT, Perplexity and Google, 95 checks in all, and recorded two things for each: which agencies were named, and which websites the engine cited to justify them. The answers were not random. Three mechanisms explained all of them, and each one points to a different thing a local business has to do.

How was the study run?

• 63 questions across seven intents: local ("best marketing agency in Suwanee GA"), vertical ("chiropractor marketing agency in Georgia"), attribute ("agencies that charge a flat fee instead of a percentage of ad spend"), AEO, cost, problem and comparison.
• Perplexity: all 63, with verification re-runs logged out, because a logged-in account with memory produced five false positives for our own brand that disappeared when logged out.
• ChatGPT: 20 questions in Temporary Chat, memory off.
• Google: 13 questions, recording the AI Overview, its source chips, and the local pack.
• Scoring: named in the answer, cited as a source, or absent. Every row, with the agencies named and the domains cited, is kept in a spreadsheet we will share on request.

We are a marketing agency and our own brand was one of the things measured, so the study is not neutral about us; the method is disclosed so you can repeat it.

Mechanism one: local questions are answered from Google ratings, not websites

For "best digital marketing agency in Suwanee GA" ChatGPT did not summarise web pages. It rendered a map panel, and every agency in it carried a visible 4.8 to 5.0 star rating. Google's local pack for the same question led with two agencies in one coworking building on Buford Highway, rated 5.0 from 65 reviews and 5.0 from 14. A third agency in the same building, with a new profile and no reviews, appeared in one pack labelled "No reviews" and in no others. Nothing on any of the three websites explained the order; the review count did.

Implication: for a local agency query the website is not the bottleneck. A Google Business Profile with roughly fourteen five-star reviews enters the set and sixty-plus leads it.

Mechanism two: attribute questions are answered from the vendors' own pages

"Which agencies charge a flat monthly fee instead of a percentage of ad spend?" produced a table of ten agencies on ChatGPT and seven on Perplexity, each with a published price in a column, and every single row was cited to that agency's own pricing page. No directory, no listicle. The same pattern held for "agency with no long-term contract", "agency that lets me keep my ad account", "agencies that run Meta instant-form lead ads" and "who offers an AI visibility audit that scores a website".

Implication: a page that states the attribute as a checkable fact, with a number, is eligible immediately. A page that says "transparent pricing" without a figure is not.

Mechanism three: category questions are rebuilt from third-party lists

"Best med spa marketing agency Atlanta" and "best marketing agency in Gwinnett County" were answered from lists: Clutch, The Manifest, Expertise.com, ClearlyRated, Guide to Gwinnett, and, for Perplexity's first Gwinnett pick, the Gwinnett Chamber member directory. Agencies' own self-published comparison articles were cited as readily as independent ones; Gemini has previously said out loud that one agency "self-publishes its #1 ranking" and cited it anyway. Google's AI Overview for the Gwinnett question used our own disclosed comparison as its source chip one week after it was published.

Implication: get into the lists that exist, and publish a methodology-disclosed comparison of your own category, because the engines treat it as a list.

Which sources were cited most?

What did not matter?

• Crawler access. Our site serves byte-identical pages to GPTBot, ClaudeBot, PerplexityBot and a browser, and has for months; it changed nothing for local questions.
• Schema on its own. Every page on our site carries Organization, Service, FAQPage and Article markup; it made pages eligible, not chosen.
• Generic how-to content. For questions like "why are my Facebook ads not working" no agency was named by any engine and our guides were not cited; the answers came from large publishers and Reddit.

What should a local business do, in order?

• Google reviews first. Every local query is rating-gated and no website work substitutes.
• One page per checkable attribute you can state as a number: price, contract term, account ownership, a named audit.
• Get listed where the engines already look: the chamber directory, Clutch, The Manifest, Expertise.com.
• Publish a disclosed comparison of your own category, with a real table and your own entry, honestly marked.
• Measure citations by engine and question monthly, logged out, because memory on a logged-in account invents results.

How we score the website half is in what the AI Visibility Scan measures; how the local half works is in how AI decides the best marketing company near me; and the broader playbook is in how to get your business recommended by ChatGPT and other AI.

Engage Ads runs paid advertising, AI search visibility and lead follow-up as one system for high-ticket service businesses in Gwinnett County and across metro Atlanta, on a flat monthly fee with the ad accounts in your name. If you want to see where yours is leaking, start with a no-cost growth audit.

The study is what our own method is built on. See how we apply it as a service.