The various fields, check boxes, radio buttons, and other functions that can be added to contact forms should be allowed within the shopping cart customer details.  Being able to select a drop down menu for an additional question, or checking off a radio button could have a use and make the shopping cart have more functionality.  Also the ability to create fields and move them up and merge them between some of the preset fields could be helpful for asking for related information to the previous field - if needed.

For example, something like: Send a quote first checkbox.  With custom made products, sometimes this is a good thing.  Of if expensive shipping could occur for shipments outside the country.  Most people want to know what a shipping cost is first before shipping outside the USA.

Thanks,