Add an image to a line item in drupal commerce my client ask a site to sell printed canvas so I need to allow site users to add at least one image to every drupal commerce line item. 

There is easier to start from a drupal kickstarter installation or a clean installation od drupal + commerce module?
There is some module to achieve this with drupal commerce?

Thank you
It's easier to start with kickstart, but there are alot of things in there you might not need and confuse you in the process of setting up your store.

I would suggest just going as minimal as possible and add in what you need for the site as needed. I'd say just go with the core Commerce module and work your way up and add in the things as you need it to reduce all the bloat. Then you will have nice clean installation and also know where everything is as you will be done building it up from the ground up. 

I was attempting to go the kickstarter route in the beginning just as you would because I saw that it was easier, but its really not i feel as there are certain modules you just dont need.