Architect Arithmetic challenge

hi there!
i have finished the Architect Arithmetic challenge :heart_eyes:
can you please give me your feedback

static void Main(string[] args)
        {
            Console.WriteLine("What monument would you like to work with?( TAJ MAHAL or AL HARAM )");
            string answer = Console.ReadLine();
            answer = answer.ToUpper();

            switch (answer)
            {
                //---------------------
                case "TAJ MAHAL":
                    CalculateTotalCost(answer);
                    break;
                //---------------------
                case "AL HARAM":
                    CalculateTotalCost(answer);
                    break;
                //---------------------
                default:
                    Console.WriteLine("Error, please restart the program");
                    break;
                //---------------------
            }
        }
        static double CalculateTotalCost(string Building)
        {
            switch (Building)
            {
                case "TAJ MAHAL":
                    double triArea = 24 * 24 * 2 * 4;
                    double totalArea = 90.5 * 90.5 - triArea;
                    double price = totalArea * 180;
                    Console.WriteLine($"{price} poses");
                    return price;
                    

                case "AL HARAM":
                    double triArea2 = 264 * 84 / 2;
                    double bigRectArea = 284 * 264 - triArea2;
                    double smallRectArea = 180 * 106;
                    double totalArea2 = bigRectArea + smallRectArea;
                    double price2 = totalArea2 * 180;
                    Console.WriteLine($"{price2} poses");
                    return price2;
     
                    

                default:
                    Console.WriteLine("error");
                    return 0;
            }
        }