Exceptions such as quantity excess in material requests and purchase orders, purchase price escalations are automatically highlighted. You can control cost overruns before they occur.
NT items often make up to 30% of a project. ProjectBase tracks them automatically from purchases, so you will never miss billing customers completely for all NT work.
Material Requests and Purchase Orders are linked to cost estimates (BOM). So there won't be excess purchases. Plus, leftover materials are effectively tracked and used in upcoming projects.