It varies and really difficult to say any specific figure on this case. But your pay scale increases directly with the number of projects and years of experience, you have. One thing you must remember that SEO is not an overnight success machine. You have to work hard, you have to build skills, you have to have patience, you have to have dedication, you have to have consistency, and above all, you have to have a target in life and a vision which will drive you to reach your goal.