It makes no sense. How do you know if a shirt hanging on a clothes rack is worth $20 or $100? You don't unless there's a price tag on it and someone pays that price, or it doesn't sell and eventually has to go on the clearance rack.
In the same manner, what is the price of a piece of property? Sure, you can get an appraisal done on the property, which I would think any bank making a loan on a building would do. But really, you don't know what the price of a building is until the owner puts a price tag on it for sale. And even then, you really don't know the price until it sells.
I can tell you right now the county has appraised my home and land for half of what it's really worth. You think I'm going to complain about that since my property taxes are based upon the value from the county accessors office? No way!
Trump buys a building for $20M, he then claims later on it's worth $100M, who's to say it's not? Maybe he's overvalued it, maybe he's undervalued it. There's no way to truly know.
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