We can easily break this down into four triangles. There will be one on the top right, bottom left and also in opposite corners. Using the formula A = 1/2bh, we can find that the area of the four triangles are 1120, 2063, 16091 and 21689. If we add up the area of the four triangles, we get 1120 + 2063 + 18091 + 21689 = 42963 ft^2. Since the total cost $168,240, we know the cost per square foot is 168240/42963 = $3.92. So in other words, Mr. Hewitt will get his land, but barely.