Through company settings you can specify how many invoice copies you want to print out when invoicing.
How to decide invoice copy numbers
Select View - Settings - Company.
Go to the Setting per Module and click Sales and Invoicing.
Select the Printouts
tab.
In the No. of copies field you can select how many copies you want to print for each invoice.
Click OK.
Next time you invoice you will have the selected numbers of invoices printed out.
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