If Trump overestimated for his properties doesn't that mean he paid too much in taxes? If so is the state and fed going to give money back?

So a bank or any lender for that matter will make their own appraisal . They do not take your word for it . Ask any banker .

Property is appraised by the Lender - for a loan application.

The Government Entities such as the city or county might appraise the property for its tax value, to assess taxes, but the taxable value is generally not its loan value.

In all cases, a property is worth whatever someone is willing to pay for it.

Example - I want to sell my house and 5 acres, and I want to sell it for 300K. You say you are interested but that you would be willing to pay me 275K - which is 25K less than I ask for. I could take you up on that offer or make a counter offer to sell for 290K which is 10K less than I asked for. You could take my offer, or reject it, or make an offer for 289K. You see that is call negoiation . So no dumb *** Judge can declare what the value of a property is. It is ALWAYS worth what someone will pay for it.