Deductions & credits

In step 9, if by saying yes do you mean yes to checking box "Your percentage of business use of the vehicle varied over the years" and then yes to converting this asset to nonbusiness use?
If I say yes here, the questions ends here and it just goes back to vehicle summary.
It doesn't ask any more questions, not even sale price of the vehicle or anything.

Does the purchase price matter? It was purchased for personal use years before it was placed in service for the business. I thought you use the FMV price of when it was converted for business use.

Do I need the average business percentage over ownership? I don't remember how much I paid for the vehicle and what the miles were.

The average business percentage since it was converted to business use is 75%.