There are three main areas to estimate before your project starts–effort, duration, and cost. Of the three, you must estimate effort first to understand the total amount of work. The duration can be estimated once you have the effort and the resources that you can apply. For example, if you have a project that you are estimating to be 800 effort hours, the duration will depend on the resources that you can apply. If you only have one person, the duration might be six months. If you have three people, the effort might be three months or less.
Once you understand the resources that you can apply to the project, you are in a position to create the cost estimate. At a high-level, project costs are estimated by looking at labor and non-labor items.
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