Before ordering, verify the rough-in distance (outlet axis to wall) against the plumbing drawings; a mismatch here is the most common cause of returns in bulk orders. Bowl length and height should also be checked against the bathroom layout of each unit.
A dual-flush mechanism (partial and full flush) is now a practical requirement: it cuts the building's water consumption and is a selling point in volume projects. Kasra Sanitary Ware supplies its toilets with a dual-flush mechanism.
In project purchasing, pay attention to glaze quality and body water absorption; low absorption prevents glaze cracking and odor retention. Certifications such as ISO 9001 and CE indicate the manufacturer's quality consistency across large orders.