Item prices shown in the catalog do not include taxes, these are added to your order before the payment is processed. Follow the steps below to see the price breakdown of an order:
Go to your dashboard
Scroll down to find the "Recent orders" section
Click on "See all orders"
Scroll down to find your order, or use the search bar to locate it
Click on your order and scroll down to find its price breakdown
For manually placed orders, you will be able to see the taxes you're being charged at checkout, before proceeding with your payment:
What kind of tax rate am I being charged?
Tax rates vary from country to country, and within the United States, sales tax rates will depend on your customer's address for each order.