Any SEO services provider firm can be hired for the optimization purposes of the websites. These firms often charge the clients certain bucks in order to share their expertise in the perspective field. The in-house SEO is something that your own firm pursues. A group or flocks of people, who work together and share their knowledge to best, optimize the websites. But the team of search engine optimizers only works for the in-house projects and they do not accept any outside projects.