(Please do show me your website before ordering it and don't forget to read extras and description below)
If your website has W3C errors it is not good for SEO.
I can make it 100% errors FREE and w3C Validated.
Please note: $25 will be extra if your website is not simple HTML, specially Wordpress or any other CMS. Actually it requires more effort and time to find out errors in the theme files, widgets, plugins, posts and pages etc.
Admin login info or Cpanel Login info will be required.
Only that code will be fixed which will be easily reachable & editable.