Custom SEO toolkit, Mobile version of site, duplicate site

This is a project for our custom website to perform the following tasks. All code must be meticulously documented, the freelancer must be proficient in Git and commit after each task is complete, and communication is extremely important. The tasks are listed in order of decreasing complexity. 1. Create an SEO toolkit and custom, seo friendly URL generation for all of our pages. Seo toolkit will include custom meta tags and customizable on site SEO configuration. 2. Create a mobile version of our site that detects mobile browsers and automatically switches the user. 3. Finish building a duplicate site that will be used for other purposes. 4. Create custom 404 pages for marketing purposes.