finding cheaper Car Key Chips
 

i have a bmw e46 car .in case lost my key ,i want to get a Car Key Chips which can match a new key ,by contrast ,found YH Key for BMW is more cheaper than other !!!

You wont find one. You may as well just fork over the cash for the BMW keys. The chips have a unique code in them which is read by a transponder in the ignition. If the code doesnt match the car wont start. The only way to gaurentee that the key will start the car is to get a genuine BMW one.