Website for Online test series

I am looking to get a website developed for an online test series. I am fairly certain I need an e-commerce website, but need some special features that would support an effective workflow. I am particularly interested in having it developed on the Codeigniter PHP platform.

I am open to any and all suggestions on how to make this project stand out and really give users an exceptional experience, so that we can launch the website for my online test series with success. By working with a Freelancer.com partner, I am sure that together, we can create an amazing e-commerce platform that will meet all my needs and exceed user expectations.