The 2003 Suzuki Wagon R is moderately easy to maintain. Changing the engine air filter is no problem, as you only have to disengage a few fasteners for access to the filter. The headlight bulb is no problem to change, as you only have to reach behind the housing for reliable access to the bulb. The components of the spare tire are easily accessible in the rear of the vehicle, keeping them ready to go in case of emergency.
Some things are problematic on the 2003 Suzuki Wagon. The engine coolant reservoir is located deep in the engine bay, making it hard to reliably check the level markers. You will need to use a few tools in order to remove the center brake light assembly. Changing the tail light bulb will require you to remove the entire housing first, which will demand some bolt removals and a bit of force.
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.