The financial disclosure form values many of Trump's courses at two to four times the multiples of annual revenue other courses command, in an industry where most operators struggle to make profits, according to golf course appraisers. An industry rule of thumb is that courses are worth 1 to 1.5 times their annual revenue.

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Trump reported combined revenue of less than $160 million, excluding the Miami resort, which doesn't break out golf-related revenue, and land sales at the Los Angeles property. Based on the industry standard valuation metric, that would put the value of Trump's golf empire closer to $160 million to $250 million.



Buddie Johnson, a Phoenix, Arizona-based golf course developer and appraiser who wrote the book, "Analysis and Evaluation of Golf Courses and Country Clubs", said of Trump's golf course valuations, "Stacking it up against the universe of other golf course sales he is kind of off the charts. Anyone can say anything ... such is his verbosity that when he talks about the valuation of his golf clubs he talks louder than anyone else, and he thinks that makes it true."

In 2014, the average multiple of golf course sales was 1.4 times revenue, according to a recent survey from the Society of Golf Appraisers.



"Everyone thinks they can do better than the other guy, and people buy [golf courses] for ego," said Jeff Dugas, who has appraised 2,000 courses and is a partner at Cheshire, Connecticut-based Wellspeak, Dugas & Kane.



The Trump campaign and Trump Organization did not immediately respond to a CNBC request for comment.



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The common element in many of Trump's golf valuations is that he assumes he has multiplied the value of his clubs once he has poured money into renovations, appraisers said.

But that is a common fallacy in the golf business, where the price of capital improvements rarely, if ever, carries through to the bottom line.

"Golf courses are like new cars," said Larry Hirsh, a founder of the Society of Golf Appraisers and president of Golf Property Analysts in Conshohocken, Pennsylvania. "You drive them off the lot and they're worth half as much."

The experts would not comment on Trump's course valuations specifically because the disclosures were not complete enough to estimate an exact value—revenue helped provide a ballpark but is not precise enough.