Improve my existing custom coded CRM system

I built a system to handle orders for my websites. It's based in PHP/MySQL but needs to be revamped and improved so it runs more efficiently. I also need to add on more features so this will be an ongoing job. Please apply to this job if: - You know how to organize and improve existing code - Very proficient in PHP/MySQL - Have worked with custom CRM systems - Familiar with the [login to view URL] API