Florida CPA firms are licensed by the Board of Accountancy under Chapter 473 of the Florida Statutes; a firm using the CPA designation needs a firm license, so a non-CPA buyer can take over the client base but not the CPA firm name. Florida has no state registration for tax preparers or bookkeepers beyond the IRS PTIN, and no sale-specific board rule on client files that we could find. Two provisions do apply: working papers remain the CPA's property unless agreed otherwise (F.S. §473.318), and client records must be furnished to a client on request (Rule 61H1-23.002).
For AICPA members, interpretation 1.400.205 governs the sale: a written consent request to each client, consent presumed after at least 90 days, no file transfer before then, and return of records not sold. Tax return information may be reviewed by a prospective buyer under a written confidentiality agreement (Treas. Reg. §301.7216-2(n)). Florida's Sunbiz records make it simple to confirm the seller's entity, officers, and registered agent before a letter of intent.
Sources: Florida Statutes §473.318 · Fla. Admin. Code 61H1-23.002 · AICPA Code, ET §1.400.205 (PDF) · 26 CFR 301.7216-2