No Biz or Farm activity? No rental to others to graze their cattle? (Is he lying about that income?) Why build fences on property that has no animals on it?
Then you get reimbursed by the DofA for building these fences Cool. The government does not reimburse me when I put up fences, so why does it reimburse him? The quick answer is he filed the application and made statements to the DofA that got him approved for the money. Get a copy of the grant application.
Then your client lied to you about receiving the money. "He Forgot" that is why it is on the Transcript, and I presume you are dealing with a CP-2000 issue.
I like Edsel's answer above. When he starts a farm, Biz or Rental, then he can depreciate his basis. Until then, he has to pay tax on the grant.
He can't use it to reduce his basis in the property, because he isn't using the property for Farm, Biz or Rental, and it wasn't an easement, he didn't give anything up. He got something.
Rich