The 2008 BMW X3 3.0si is a moderately difficult vehicle to maintain, and will require many tools to complete its repairs. Changing the fog light will require you to completely remove the air filter housing first. Other models will not require this step. You will have to lower the tire from under the vehicle for access to it. Changing one of the tail light bulbs with reliability can be a problem, as you will have to remove many fasteners and use many tools to complete.
Some things are easier on the 2008 BMW X3 3.0si. Changing the engine air filter with reliability is easy, as you only have to disengage a few fasteners for access to the filter. These fasteners are easy to disengage. Similarly, the cabin air filter is also easy to change. No tools will be required. The brake fluid reservoir is easily visible in the engine bay. This will allow you to check and replenish the fluid level on a regular basis.
Hans Angermeier has produced over 100,000 videos showing drivers how to fix things on their cars. He has broad expertise on basic repair procedures covering the majority of cars on the road.