I have an accountant pro -- individual CPA with a fairly large client base (30 years) who would like me to "service his customer expansion" needs.
How many new clients and what types of clients (individual, business)? Local? Here is a pick list of strategies I know work: If he has a large, satisfied base, use them for referrals and to get their friends to seminars that he hosts. He could partner with a stock brokerage firm (they usually don't do taxes) and do joint marketing (education-based meetings on minimizing taxes, increasing business cash flow, etc.), partner with a legal firm and do joint marketing, their own meeting titled "How to read your business financial statements like a CPA" or "10 ways to get more cash flow out of your business". I have a long list on this topic so connect and I am happy to share.