काकणीद्वयं चास्य पलवेतनम् ॥ कZ_०४.१.४२ ॥
kākaṇīdvayaṃ cāsya palavetanam
याच्या पल-परिमाणाच्या कामाचे वेतन दोन काकणी आहे.
Different materials/processes can require more labor, fuel, time, or expertise; a published differential fee reduces discretionary overcharging.