From showcase website to e-commerce website I have a big Drupal 7 showcase website, that needs to evolve in a e-commerce website. I know Drupal e-commerce but I don't know if it's ("easily") possible to upgrade a content type to a "product" content type that can be added to a shopping cart?
In order to do that, here is what I did :
 - install Drupal Commerce 
 - create the product (name, ref and price) 
 - and add the product reference field to the existing product

If that can help...