Adjusting headlights beams
 

Is there a way to check/regulate this at home, point to garage door/wall, rather than taking car to the shop? I ask because my left hand side light beam appears very low compared to the right hand side and it should be the other way round (I am in the UK), so I may need to adjust it.

Try Daniel Stern's website

http://www.danielsternlighting.com/tech/aim/aim.html

Which car do you have? I think you need a 7mm allen on most all mercedes, or sometimes you can turn them with your fingers if they are strong.

E320 W210, and my in-laws garage doors and driveway will be used for the alignment, as I live on a hill and is impossible to find a level area to do this.

Adjust the light up a bit, then drive on the motorway and see how you like, it. Then adjust from there. You dont need a level surface if you just want to "rough" it in!