Accountants work under more advertising scrutiny than most small businesses. State boards of accountancy regulate who may use the CPA title, how a firm name may read when not every owner is licensed, and whether claims on the site could be seen as deceptive. Some states also limit how client praise and endorsements may be quoted. None of this is legal advice, and your own board's rules come first, but a designer should know these questions exist and ask them before writing copy.
Data you should never collect through a contact form
Tax preparers fall under the federal Safeguards Rule, which expects a written plan for protecting client information. A plain website form that invites people to type a Social Security number or attach last year's return undercuts that plan. The site should collect only a name, a way to reach the person and a short description of the need, then move documents into a proper secure portal.
Accessibility and plain reading
Many clients are older, and many read on a phone in a parking lot. Readable type, strong contrast, labeled form fields and pages that work with a screen reader are part of serving them, and they lower the chance of an accessibility complaint.