Special functionnalities

[Fred_be]

Hello

I'm looking for an e-Commerce solution, and heard some good stuff about Prestashop.

I want the solution I'll choose to be able to do the following :

- to give the user the ability to upload a file when he orders some particular articles.
- to calculate automatically the price of some articles when user orders
For instance, users orders 100 items A. Based on this, the price of the item B would be calculated on basis of a fixed price (20 euros) + 100 x 0.5 euros, for example.
Is Prestashop able to do this ?

Thanks in advance for your reply