Yes, you can take the standard sales tax in your area based on your income and add the sales tax on large purchases such as an auto, boat or plane. In Turbo Tax, click on the Federal tab, select Deductions and Credits, go down the list to Estimates and Other Taxes Paid. Look for the line titled Sales Tax. Click on the Start button to the right (or the Update button). You'll see a comparison screen showing you your state incomes taxes paid and an estimated standard sales tax paid. Click on the button that says "Try Sales Tax Anyways".
Follow the questions and select the Easy guide. Continue through that part of the interview. It will ask your local sales tax rate and information on your larger purchases. When you finish this section, Turbo Tax will calculate and compare your now larger sales tax deduction to your state income tax deduction and chose the one which results in you paying the lowest tax allowed on your return.
Remember, you can deduct either sales tax or state income taxes on your return but not both.
