The point is that...
1) You can't deduct a loss as a business expense because you used personal funds (post-tax) to buy the car.
2) You won't [ever?!] have a gain on a normal vehicle used personally or in business.
3) You can't deduct a loss on a personal vehicle anywhere, because you just consumed something. The IRS only taxes income, it doesn't deduct consumption.
so...
I don't see much point in helping you with your calculation, unless I can think of some reason it might affect your taxes. Just don't show a GAIN on the sale of your vehicle anywhere and you should be fine, unless I'm missing something 🙂
In other words, for the sake of taxes and AMT taxes a $1 personal loss is the same as a $1000 personal loss--irrelevant. The IRS only cares if you had a gain and they can tax it. In that case, they want to recoup the depreciation you took in the standard mileage on your business when the car didn't really depreciate, but instead appreciated (e.g., increased in value) and they want to recoup that depreciation at the same rate you deducted it--ordinary income rates, not lower capital gain rates.
