Product Cart Development

I need to add some functionaly to the build-to-order section of Product Cart. At the bottom of the page I need the user to be able to select an option that will add a service fee based on the total price of the selections they have made above. Here's a sample page: [login to view URL] Below the last category I want a new category added called "System Design & Programming". In this category the user can select none, or "full system design and programming". The price for the second option should be calculated in real-time as they make selections on the page. I have posted this project twice and both times the providers have failed to even start. If you are not capable of completing this project please don't bid.