Unless you have a source for discounted materials the cheapest way I can think of is building wall panels (either plywood or OSB) and covering them with a material called silver shrink. It comes in a 54" x 30' roll and you tack it on then heat it with a heat gun. The cost is $136.75 per roll from BMI Supply.
Design wise, from what I can tell, these mazes are based off of equilateral triangles much like that triangular grid system used in some haunts. All the angles would be 60 degrees.