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On this tab, you can specify the default terms to be used under this contract.
The "Contract (create)" form. The Terms tab
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In the Maximum Reservation Period (Days) field, enter the maximum number of days that the goods can be reserved for this company.
Select the Use Phased Revenue Recognition option to be able to recognize revenues on each stage (or phase) of long-term projects  according to IFRS 15.
Select the Apply Retention check box to indicate to the system that final payment retention must be applied to this contract of the company.
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