Fair Market Value of inherited van

We inherited a van from my wife's father in 2014 and we had sporadic business use of the van over the years.

 

We traded in that van for $5K in 2021.  And did not use it for business at all in 2021.

 

Now TurboTax is asking all kinds of questions about it, and I have most of it figured out.

 

What I have down is this:  Sales price 0.00 (5000.00 X 0% usage = 0.00)

 

Vehicle Total Cost:  ?????   

Do I put down 0.00 since we inherited it?  Or somehow figure Fair Market Value?  And where can I find the FMV for 2014 for this vehicle?

 

Basis for Gain/loss

I'm assuming 0.00 goes here, since we did not trade in listed property?  Right?

 

Prior Depreciation Equivalent:  I have the depreciation tables, and I can calculate this--just haven't yet.

 

So to summarize, My questions are:

  1. What to put down for fair market value of this inherited van?
  2. Basis for gain/loss, if any.
  3. And is all this really necessary?  TurboTax seemed to balk on MACRS for this vehicle later when it was checking things over, so I am assuming that has something to do with this.

Thanks for any help you can give.