Profit Percentage for Inventory is sales Invoices

we are selling all our products on a profit margin of 10%. Can we fix this percentage in manager so that whenever i prepare a sales invoice , the sales price of the product automatically come with added 10% profit of purchase value.

Thank you

No. But you can set sales prices for inventory items in the Inventory Items tab that include whatever markup you desire.

If you want to change the selling prices, Batch Update is a convenient method. That way, you can use a spreadsheet to set and adjust prices, then update them as a batch. See Use Batch Create and Batch Update functions | Manager.