odoo8 product note notifier

In Odoo8, in the purchase order I need to see a "note for purchases" regardings each product. I.e. inserting a new raw when I select a product I need to be notified if this product have a "note for purchases". This notes is a text with some annotation i.e., the minimum price to have some discount, or that product need others accessories and so on... This "alert" could be made via a pupup windows or a additional field in the grid that indicates that the product have some "note for purchases". The module should add the text field in the product window and add the code to notify if there is some note regarding the current product.