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The time sheet register can be viewed in either units, hours or minutes. 
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This can be edited by going to settings > my settings. Do not use appliance settings > time billing as this only changes the settings for future users.
The default time units also affects the 'Enter Time Records' screen. 
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You can find more information on the Time Billing Register page.
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Invoicing is the step that will create a bill for the client after you have entered time or fixed fees and any recoveries. There are various statuses of invoices which must be paid close attention.
These are detailed more on the Invoicenvoice Register page.
External Accounting
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