Advanced PHP 5 knowledge
Model View Controller design pattern
You must be an expert in these skills. Please do not bid and then tell me later you can learn as you go. This is a very complicated website and the learning curve will be steep.
Initially, your bid is for to "look around" the back end and grasp what needs to be done. So initially, I've budgetted for about 4 h0urs of consultation before we move foward with actual work. So please bid based on that.