I highly recommend you do some reading to get educated on being a sole proprietor. As for vehicle deductions you will have several options based on your income & other expenses so there is no straight forward answer to give you that is why sitting down with a local pro or doing some reading before doing anything so you get it right the first time.
About Publication 334, Tax Guide for Small Business (For Individuals Who Use Schedule C or C-EZ)
About Publication 463, Travel, Entertainment, Gift, and Car Expenses
About Publication 535, Business Expenses
Other Current Products
