You should have records on the value they gave you for the car you traded in. "Traded in" refers to trading one vehicle in toward the purchase of another but you said above you didn't buy the new car? They would have given you a written sales document to use for this purpose.
You may be able to go back to the location where you sold/traded in the car and see if they have a duplicate of the sales transaction that you can use.
You will have to show a sale of your vehicle since it was used for business use on your tax return showing your "adjusted" cost basis and showing your trade in or sale value received for it.
The adjusted basis will have to be adjusted for the depreciation component of standard mileage rate if you used standard mileage rate or by the depreciation allowed or allowable on it if you deducted actual expenses.
When you either took depreciation or standard mileage rate on the car used for Uber Eats, then you also took depreciation on the car. You will have to adjust the basis of the car traded in by the depreciation component portion of each standard mile driven or the depreciation deducted if you took actual expenses.
Costs included in the standard mileage rate
The standard mileage rate can be used as a substitute for actual expenses for the following items.
•Depreciation
•Lease payments.
•Maintenance and repairs.
•Gas and oil.
•Insurance.
•Vehicle registration fees.
Depreciation component of standard mileage rate.
For computing the taxpayer’s basis in an automobile, the standard mile-age rate has a component that represents depreciation.
For 2020, the depreciation component is 27¢ per mile.
If the actual expense method is used in any year after the standard mileage rate method has been used, the straight-line method of depreciation must be used. (Rev. Proc. 2004-64)
Depreciation Component of the Standard Mileage Rate
Year.....................2020..........2019..........2018..........2017..........2016
Rate per mile..........27¢..........26¢..........25¢..............25¢.............24¢
Note: These rates do not apply for any year in which the actual expenses method was used.
Depreciation beyond zero. The taxpayer must reduce the basis of an automobile by the depreciation component of the standard mileage rate, but the basis cannot go below zero
