Even if you have a working partner that may fill one or more roles in the business, it's always a good idea to have an advisory board.

It is okay for you or your partners to fill these roles, but it's unlikely that all of the roles of an advisory board can be filled by the management of a small business.

Even if all the advisory roles can be filled by management, it's still a very good idea to have people outside of management to bounce ideas off of. There are many opportunities to have an advisory board that will either cost nothing or very little, develop a relationship with the following professionals and have them be part of the advisory board, or even suggest other members to be on the advisory board: 

1. CPA
2. An Attorney/Lawyer  
3. Insurance Agent
4. CFO
5. Someone with technical expertise in your field

Do everything you can to build the right relationships and to promise giving business to these professionals either now or down the line. Of course, I have a business associate who says he never has or never worries about any problems in his business. The reason is he gives all of his problems to his advisory board and lets them figure it out and lets them assume all of his worries. Advisory boards can be very helpful and it is worth the time and energy to build the right one.