I have used art foam sheets. They are about 1/8" thick, come in many road colors. This is almost like a foam rubber. It does glue nicely, you can paint on it and it is cheap. The sheets I have come in 11"X17" sheets and are very flexible for hills and such. With landscaping on both sides it really does look real. I am not sure where you get it now but I am sure it would be like in crafts stores and such. I would send you a picture but I am trying to find my pictures. Also there is some mini pinstriping tape that I used for center lines. It looked good for quite awhile but eventually dried out and pealed off.