The price depends on the style and type of the image. I would do them as cheap as poss tho. If it was one colour for an a4 sheet, i would only charge round a fiver, and that would be your own design and for me to lay it out.
I can make up your own design or if you want to supply artwork then thats fine. The format would be prefered as an ai vetored eps file.
The etched glass vinyl would be a bit more pricy as its a specialist vinyl. But for instance i could do you say 3 window stickers saying golfgti.co.uk for about £4.
If everyone comes up with a layut they want then i can do say a product list and people can just order it off that. I could post the list. What do you think?
Dan