<?php
if ($_SERVER["REQUEST_METHOD"] === "POST") {
  // Retrieve form data
  $landType = $_POST['land_type'];
  $landSize = $_POST['land_size'];
  $foundationDepth = $_POST['foundation_depth'];
  $buildingSpecification = $_POST['building_specification'];
  $parapet = isset($_POST['parapet']) ? $_POST['parapet'] : "";
  $numberOfRooms = $_POST['number_of_rooms'];
  $roomType = $_POST['room_type'];
  $bedroomSize = $_POST['bedroom_size'];

  // Perform calculations and generate estimates based on the form inputs
  // ...

  // Display the estimated results to the user
  // ...
  echo "<h2>Estimation Results:</h2>";
  echo "<p>Land Type: $landType</p>";
  echo "<p>Land Size: $landSize</p>";
  echo "<p>Foundation Depth: $foundationDepth</p>";
  echo "<p>Building Specification: $buildingSpecification</p>";
  echo "<p>Parapet: $parapet</p>";
  echo "<p>Number of Rooms: $numberOfRooms</p>";
  echo "<p>Room Type: $roomType</p>";
  echo "<p>Bedroom Size: $bedroomSize</p>";
  // Display the estimated quantities of materials or any other relevant information
  // ...
}
?>