In preparing the sixth edition of Estimating Construction Costs the author has retained the fundamental concepts of estimating that have made the book successful for many years. All of the example problems have been revised with more explanations regarding assumptions used in the calculations. This edition has reorganized and consolidated chapters to increase the clarity of the subject matter for the reader. Extensive new sections have been added on equipment, including graders equipped with GPS, and methods of calculating depreciation, investment, and operating costs of construction equipment. The computer estimating chapter is revised with additional material on the use of computers in preparing estimates for bidding purposes.