How do you estimate project costs?

As you learned earlier, customers and stakeholders expect project managers to deliver a definitive and functional cost estimate in a timely manner. How do project managers do this? Good question. As you read, there are three levels of estimation in a project: the WAG, the SWAG, and the you bet your job on this figure estimates. Actually, they are referred to in industry as, the Order of Magnitude the Budget, and the Definitive cost estimates. The PMBOK addresses them under Analogous, Parametric, and Bottom-up estimates respectively Explain which of the three is used where in the project lifecycle.