Different cars have different locking mechanisms. This is why some cars may be more difficult to unlock han others. Some cars may have a sliding mechanism which needs to be grabbed and pulled up in order to unlock the car. Some cars may be unlocked by pressing an unlock button on the driver’s side door handle, while other cars may be unlocked by using a special tool to grab the door handle. Some cars such as certain BMW’s and cadillacs must be unlocked using a very specific procedure such as hitting the unlock button on the center console, followed by using a special tool to grab the door lever, and finally using a special tool to grab the sliding mechanism which locks and unlocks the door.