When selecting an SEO agency, it is important to consider the agency's reputation, experience, services offered, communication practices, and past client success. The ideal agency will have experience working with local businesses, provide on-page and off-page optimization strategies aligned with goals, offer flexible budget-friendly plans, and demonstrate client success through case studies and reviews. It is best to interview several agencies, asking about processes, reporting, and previous work. While DIY SEO or freelancers are alternatives, an experienced full-service agency can help small businesses achieve long-term online visibility goals.