Custom PHP template integration

I have a html template [about 4 pages for the first part] which needs to be integrated with our websites data. We use custom PHP and a simple replaceable templates design. Some of the pages are as simple as just replacing the values while some will have a bit more logic to it. A simple outline of the tasks: Page 1: Change the flow of registration and modify the logic that exists. Page 2: Allow user to upgrade to a different level. Page 3: Display a tree and allow users to navigate through the tree, choose certain elements Page 4: Display data and aggregates from the database Only Page 3 might need a bit of logic around it. Please place a ballpark figure with your availability. The task is not complex but I want someone who can see it from start to end. More information will be provided on