Changing light bulbs in your car is not as easy as it used to be. In some vehicles, you actually have to remove the entire front bumper in order to access the light bulb.
Light bulbs are not serviceable, you simply replace them when they go bad. You have to put the correct bulb that matches the vehicle manufacturer's specifications (Holagen or HID). In some of the newer vehicles, there is a "pairing" or "marrying" sequence that must be performed at the time of replacement. It may seem easy to do when watching a Youtube video, but a small mistake could cost you the entire headlight assembly. The average cost to replace a headlight assembly is $250 - $700 on a regular vehicle. Some of the more luxury vehicles, that have adaptive headlight systems, can cost more than $2,000.
The moral of the story is that when it comes to working on your car, in most cases, you're better off paying a skilled technician to do the job.