Business owners quite often use the standard mileage rate instead of actual expenses when taking a deduction for the business use of their vehicle. The standard mileage rate is determined annually by the IRS using data from a study conducted by an independent contractor of vehicle-operating expenses based on the prior year’s costs. The operating-expenses, which cannot be deducted when the standard rate is being used, include (Rev Proc 2002-61, Sec. 5.04, 2002-39 IRB 616):

What business owners using the standard mileage rate frequently overlook is that parking and tolls, as well as state and local property taxes paid for the vehicle, attributable to business use, may be deducted in addition to the standard mileage rate. However, the taxes do not include sales tax which must be capitalized as part of the cost of the vehicle.

And, regardless of whether the standard mileage rate or actual expense method is used, a self-employed taxpayer may also deduct on their Schedule C the business-use portion of interest paid on an auto loan.

Plug-in Electric Vehicle - the business use portion of the credit becomes part of the general business credit (form 3800) with its normal carryback and carryforward provisions.