Business & farm

The sales price is $81 for the business percentage according to you. You can enter depreciation in both boxes.  

• Did you use depreciation or standard mileage rate (SMR) for the car while you used it for business? 

It would seem you have already determined the business use percentage (life of the vehicle: business miles divided by total miles on the vehicle when traded).  Based on your numbers you have a sales price for business of $81.  The cost basis was what you actually paid for the 2004 Honda times the business use percentage (16.2% per your numbers) and either the actual depreciation expense used on your return for the life of the car or the depreciation portion of all business miles.  See the chart below to calculate SMR depreciation.

The gain cannot be greater than you actual gain on the sale.

Business percentage of each number: Selling price - (cost less depreciation) = gain on the sale.

To record the sale in TurboTax assuming the car is listed in your business schedule.

The way to report the sale or trade-in, (trade is not recognized by the IRS any longer for equipment or vehicles) is as follows. You have all the records so it should provide you the detail to move forward.

1. All business miles for all years and then total miles for all years - divide business miles by total miles to arrive at your overall business use percentage for the life of the vehicle. You will use this percentage times the selling price (trade-in value) to arrive at the business selling price. 
2. Calculate the standard mileage rate depreciation portion for the business miles each year if that is the method you used for the expenses each year.  If not use the depreciation you actually deducted each year your vehicle was used for your business.
3. When go to the vehicle information under your business you can select 'Sold, disposed of, etc....' then do not indicate it was sold.  You must say 'Yes' it was converted to personal use.  This will eliminate any sales information in the vehicle itself.
4. Once you have completed the information in that section you will follow the steps below to enter your sale:
   1. Go to Other Business Situations
   2. Scroll to Sale of  Business Property
   3. On the next screen select Sales of business or rental property that you haven't already reported
   4. Use the information from step one and the depreciation from step 2 to complete your sale
5. If the personal portion of your vehicle is a loss there is nothing to report for that portion of the sale/trade.  

@bobalbertfamily