Basis of Gain/Loss is the value of the vehicle when placed into service less depreciation.
I believe you said you used the Standard Mileage rate, so you need to multiply the miles you reported in those years by the depreciation equivalent of that year.
$.30 for 2024
$.28 for 2023
$.26 for 2022
Subtract the total from the original "Placed into service" basis (value) to get the basis for gain or loss.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"