Is it reasonable to charge extra for a straightener in whole-house customization?

Whether a straightener should cost extra depends on the door panel height and the board material. When door panels exceed a certain height, especially for types prone to warping such as PET and baked enamel, installing a straightener is a standard practice to prevent warping, so the charge is reasonable; for low cabinets and small door panels, if it is pushed on you, it is unnecessary. When negotiating, ask clearly: is it required because the door panel is too tall, or is it optional, and is the unit price calculated per piece or per door. For edge banding we can use PUR edge banding or laser edge banding, and for hardware we have Blum, Hettich, DTC, Higold, and Hegu; these all affect the final quote. On price, you can first budget by wardrobe tier: basic configuration E0 particle board + PET door, Beijing 500–550 yuan/㎡, Baoding, Langfang, Xiong'an and Zhuozhou 425–467.5 yuan/㎡; mainstream configuration ENF particle board + PET door, Beijing 700–800 yuan/㎡, Baoding, Langfang, Xiong'an and Zhuozhou 595–680 yuan/㎡; upgraded configuration ENF eco board + PET door, Beijing 950–1,100 yuan/㎡, Baoding, Langfang, Xiong'an and Zhuozhou 807.5–935 yuan/㎡. The above are reference prices and do not constitute a formal quote; the actual price must be calculated based on dimensions, design, materials, hardware, quantity, and on-site conditions.