SEO my Website - open to bidding

I'm putting in place a job board target to a specific audience. I'm looking for a professional SEO that can put my jobs on a variety of U.S. job boards through SEO. In addition, I want my overall website to be ranked near the top of search engines searches for a variety of key word searches. The SEO method must be setup so that I can update or refresh the SEO tools so that my board and site stays at the top over time.