Most SEO agencies cap their retainer margins at 30 percent because of all the...

https://smart-wiki.win/index.php/Why_European_SEO_Agencies_Are_Building_Tools_Faster_Than_US_Agencies

Most SEO agencies cap their retainer margins at 30 percent because of all the manual labor involved. If you turn your internal scripts into software, you can easily push those margins past 70 percent. Build assets that scale instead of just trading time.