Virtuemart Ajax Price Update

Virtuemart has been installed and the products have additions. By choosing additions in the flypage, the total price should be shown IMMEDIATELY on the page in real time as the additions are selected (ajax). Here's a sample of what I need: [login to view URL] I should be able to use the script for future installations in other sites. Here's a similar project posted from another buyer, please review when considering bidding price.