Distru lets you create different excise tax classes for us in your invoices, along with other types of taxes (local tax, sales tax etc.)
To add taxes, go to Settings > Customize Distru > Taxes. Here you can add as many taxes as you need.
IMPORTANT: If you're synced with Quickbooks, you will want to make sure a Quickbooks Income Account is selected in Edit Tax as shown below. If you synced with Quickbooks Online after setting up tax classes, you can just come here and edit it after :
When you click Add Tax, you'll be able to select from preset taxes which have some explanation around them. Once a tax class is added, you can add it as a 'Charge' and toggle it to be a tax to any sales order.
Please note that you cannot change the name of the tax on the sales order itself, so be sure to add the tax classes within the Tax section in settings. You can, however, change the % amount. Thus you will want to create separate tax classes, such as one for arms length and non-arms length (if you happen to engage in non-arms length transactions, which is typical of micro-businesses).
Taxes, Charges and Discounts Do Not Stack
In the example above, we have an order total for $1,340.00. The line item is $1,000 with a 24% excise tax that comes out to $240. The sales tax is 10%. If the taxes stacked, you would have 1000 + 240 + 124 (10% of 1240) = 1364. But that's not the case here. The sales tax is 10% of the line item, or $1000, and is thus $100, which explains why the total is 1000 + 240 + 100 = $1,340.
Thus if you WANT TO ADD DISCOUNTS, do NOT add them as a discount in the 'Additional Charges / Discounts' section. Instead discount the line items instead. Otherwise you will have to add the discount back to the line items and calculate excise tax on that because the government does NOT let you reduce excise tax by the way of an overall discount on the whole invoice.
For more details, please check out the example here.