Masonite coated with drywall compound and painted Flo-Quill "Concrete" gives a realistic look. A lot less expensive. You can use the same technique for roads. Use 1/8" masonite for roads and 1/4" for sidewalks. Gives you a 1/8" curb height - a realistic six scale inches. Making your own allows the flexibility to make the streets and roads whatever width works for your scene.
If you apply a couple of coats of drywall compound and sand it smooth, you can score the curb lines and pour divisions in the streets. The texture lends itself to the use of chalks for wear and weather effects.
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