पुराणप्रतिसंस्कारं कर्म गुह्यमुपस्करान् ॥ कZ_०२.११.११८ ॥
purāṇapratisaṃskāraṃ karma guhyam upaskarān
(He should detect) refurbishment of old items, concealed workmanship, and (the use of) hidden tools/implements (employed for deceptive alteration).
Refurbishment can be legitimate, but undisclosed reworking distorts price, taxes, and state procurement decisions; disclosure protects revenue and trust.