At what point is it advantageous to outsource my finance and accounting needs?

My company that sells industrial materials to the construction industry has steadily grown over the years. When I founded it in 1992 I never expected to see this much success. As I added employees, I also hired a specialist who deals with all of my accounting and financial needs. However, he is set to retire within the next year and I am thinking about f&a outsourcing. The amount of work has grown to where I would really need to hire more than one person to replace his expertise anyway and I think that by outsourcing my finance and accounting needs it will take my company into the next decade and beyond. Customer service outsourcing in general seems like a good option to help my company stay within its specialty without getting bogged down in the day-in, day-out work associated with running a business. I feel that this marks a new era with my company and I hope that my son will be able to follow in my footsteps.