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If you need this functionality, you can turn on Project Costing as a feature on the Administration > Settings > General Settings form. Once the functionality is turned on, you will be able to link to projects any related documents.
The options available for Project Costing
For projects, you can specify how the material costs incurred for projects should be calculated. For this, you can use the Calculate Material Costs setting on the Administration > Settings > General Settings form.
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