WordPress Homebuying Website Development

I currently have a WordPress Web site that I would like to take to the next level. The site was built originally by a young coder who has taken a full-time job elsewhere and can't devote time to the site now - but he is still available to answer any questions about what he did. He is very bright but this was his first WordPress expereince so updatng and fixes are needed. The first thing that needs to be done is organize/update the site so we have a good foundation to build on. This includes 1) creating a staging server using a sub-domain, 2) properly organizing custom file location so the theme and plug-ins can be easily updated without breaking things, 3) reviewing Ajax/java script that is now being used and properly enqueing and making sure other best practices are implemented. If you do great work and are conciencius, you will be treated fairly and appreciated. This a small/medium project to start with but there is a long list of functionality items that needs to be done after the initial items above and there can be substantial ongoing work. You need to be familiar with Agile development and can convert user stories to code with explaination as needed. Expert at all skills related to WordPress development including: HTML, PHP, MySQL, Java Script/Ajax and ability to know and implement best practices overall.