Taxes computation can drive a lot of complexity into your invoicing process. Luckily, Hyperline can manage this for you, at no extra cost.
Click on 'Edit' in the information section of the customer page
Navigate to the 'Advanced' section and locate the 'Custom tax rate' field
Enter the desired rate and save
Navigate to Settings > Taxes of your desire invoicing entity
Click 'Set tax code'
Fill details
Navigate to Settings > Taxes of your desire invoicing entity
Click 'Add rax rate'
Fill details