this contribution allow prices break for products.
It adds a new field in the admin/product description in what you enter the discounted price per quantity in the same way you can enter the price range in the spedition module.
For example :
10? for 1 to 9 parts
8? for 10 to 99 parts
5? up to 100 parts
You enter 10 for the product price.
10:8, 100:5 in the new field.
This code automaticly add a tab at the end of the product description to show the price break to the customer.
I wrote this code because my own code is too modified to add the price break contribution.
This one is "easy" to install and don't modify lot of code.