Don't overlook these!
Updated for 2011
If you use your vehicle for both business and personal use, you can only deduct expenses that relate to the business use of the vehicle.
To allocate your vehicle's actual expenses to business use, multiply...
Reminder:
Annual operating expenses include items such as repairs and maintenance, insurance, tolls, parking fees, towing charges, interest on you vehicle loan, provided you are self-employed and not classified as an employee.
If you live in a state that assesses a personal property tax on your vehicle as part of the registration fee and you use your vehicle less than 100% for business, the business-use portion of the property tax is deductible as a business expense and the personal use portion is deductible on Schedule A and an itemized (call your state's DMV).
Determining Your Business Use Percentage:
Example:
Vehicle used from January 1st thru December 31st for business and personal use.
Result:
Car Expenses: Changing From Personal Use to Business Use During the Year