Accounting firms operate in a professional-services environment where search strategy has to fit the firm's actual services, licensing context, review obligations, seasonal workload, and client qualification process. An agency that can write pages or acquire links for another industry may still be a poor fit if it cannot explain how those constraints change the work.
The value of a new engagement can also vary materially by service line. General agency experience doesn't automatically transfer to a firm where a single new audit client might be worth $40,000 annually and where a poorly worded testimonial can create a licensing compliance issue.
What to test in the sales process: ask the agency to explain how it would separate tax, audit, advisory, bookkeeping, and local-intent searches; how it would obtain subject-matter review; and how it would prevent promotional copy from overstating results. A strong answer should describe a repeatable review process, not simply say that content will sound professional.
Compliance with AICPA ET 1.600 (advertising and solicitation standards) and relevant state board rules affects what claims your website can make. An agency that's never worked with an accounting firm may not know to flag this risk. Confirm current requirements with the applicable professional authority or counsel before relying on them as compliance advice.
Decision standard: the agency does not need to work exclusively with CPAs, but it should demonstrate that it has already thought through the firm's regulated marketing environment, client-service differences, internal approval process, and ownership requirements before asking the firm to sign.