Well there's certainly a large area to cover....
I have this habit of looking at every single sign written van for idea's and I've come to the conclusion that less is more..... Big bold letters, big phone number and maybe a very memorable website address!
I shudder when I see a van with say list upon list of what they do because it bores me and probably bores a lot of other people too.
I think it's Mike Halliday that has a van with zoo animals all over it... Completely irrelevant to carpet cleaning but I reckon it's a very clever concept because it is memorable and eye catching..... I bet kids tug at their Mum's arm when they see it and mum reads "Carpet Cleaners" and thinks "Oh, my carpets need cleaned.....!"