Your cost basis is your purchase price minus depreciation you have taken on the vehicle. You received $0 on disposal. So your loss is the purchase price minus depreciation if the vehicle was used 100% for business. If not, your loss if limited to the business use percentage. If you had it entered into TurboTax as a vehicle for past years, you will already have put in the purchase price. TurboTax will deduct the depreciation and figure the loss. If you don't have the vehicle in TurboTax you must enter it in before you can dispose of it.
