When sourcing Renault car keys, the price is heavily influenced by the transponder chip technology and keyless entry features. For older models (e.g., Clio II, Kangoo), simple ID46 transponder keys are cost-effective. For modern models (e.g., Megane IV, Kadjar), you must source 4-button smart cards with 433MHz or 868MHz frequency compatibility. Always verify if the key is a 'virgin' (unlocked) PCF79xx series chip, as 'locked' keys cannot be reprogrammed to a new VIN, rendering the investment worthless.