Its been awhile since my head was into the "Fair Tax" proposed. But, as I recall, the sales tax only applied to the first time a product was sold at retail... If still the same, then there would be no sales tax on the "used" Chevy.
"No tax on used goods. No tax on business inputs. With the FairTax, if you choose to buy any new good or service, the sales tax is charged just as state sales taxes are computed today. If you choose to buy used goods - used car, used home, used appliances - you do not pay the FairTax. If, as a business owner or farmer, you buy something for strictly business purposes (not for personal consumption), you pay no consumption tax. So, in deciding what to buy, you get to choose whether or not you pay the federal consumption tax."
"No federal sales tax up to the poverty level means progressivity like today's tax system. Furthermore, to ensure that no American pays tax on necessities, the FairTax plan provides a prepaid, monthly rebate for every registered household to cover the consumption tax spent on necessities up to the federal poverty level. This, along with several other features, is how the FairTax completely untaxes the poor, lowers the tax burden on most, while making the overall rate progressive. However, the FairTax is progressive based on lifestyle/spending choices, rather than simply punishing those taxpayers who are successful. Do you see how much freer life is with the FairTax instead of the income tax?"