In my experience, the bigger the project, the harder it is to estimate. So for the very large projects, it's important to break it down into stages and then firmly quote on each stage at it comes along (after providing a general figure for the whole project). Using an Agile planning method helps with that.
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In my experience, the bigger the project, the harder it is to estimate. So for the very large projects, it's important to break it down into stages and then firmly quote on each stage at it comes along (after providing a general figure for the whole project). Using an Agile planning method helps with that.