Trump says Mar-a-Lago is worth $1.8 billion. Not long ago, his own company thought that was over $1.7 billion too high.

After a New York judge ruled on Tuesday that Donald Trump and his company had for years used fraudulent methods to value his properties, Trump zeroed in on the ruling's section about his home: Mar-a-Lago.

"This highly partisan Democrat 'Judge' (All the Clubs, etc.) just ruled that Mar-a-Lago was WORTH just 18 Million Dollars when, in fact, it may be worth 100 times that amount," Trump wrote. In fact, the judge had cited Palm Beach County Property Appraiser valuations putting the property at between $18 million and $28 million, depending on the year, from 2011 to 2021.

Trump might think Mar-a-Lago is worth $1.8 billion, but in 2020, his own company said the Palm Beach appraiser was right. That year, the county valued Mar-a-Lago at $27 million. 

"The Petitioner agrees with the determination of the property appraiser or tax collector," a real estate broker representing Mar-a-Lago acknowledged on a form filed with the local Value Adjustment Board, and obtained by CBS News.

The broker, Michael Corbiciero, had at first filed to challenge the valuation — attesting under penalty of perjury that the filing was on the owner's behalf as the property's authorized agent — before withdrawing the petition and checking a box saying the property had been accurately appraised.

Corbiciero could not be reached for comment. Mar-a-Lago and other Trump properties are at the center of a $250 million civil lawsuit filed by New York Attorney General Letitia James. On Tuesday, ahead of a scheduled Oct. 2 trial, the judge presiding over the case found as fact that Trump and the company are liable for fraud, for overvaluing the properties by hundreds of millions of dollars — and misrepresenting Trump's worth by billions — while pursuing bank loans. The upcoming trial will now focus on other allegations in the lawsuit related to falsification of business records, issuing false financial statements, insurance fraud and conspiracy.

Corbiciero's original petition challenging the valuation does not indicate if he believed the club was valued too high or too low, but nearly all contested valuations are property owners who say the county is overvaluing, according to Becky Haltermon Robinson, a spokesperson for the Palm Beach Appraiser.

That's because local property taxes are higher for properties that are worth more. Mar-a-Lago's valuation is reflective of a property that is not a residence (even though Trump uses it as one).

"Mar-a-Lago is deed restricted as a private club. The deed itself is restricted, it can't be used for any other purpose, as such our office values it as we value the other private clubs in Palm Beach County," Haltermon Robinson said.

Deed restrictions can hurt a property's value, said Eli Beracha, the director of Florida International University's Hollo School of Real Estate.

"Clearly, when you have restrictions on a property, it'll only decrease, not increase the value of the property," Beracha said. "Every time you limit basically what the property can be, the chances are that it decreases the value."

The method the county appraiser uses for a property like Mar-a-Lago is called the income approach, which reflects the club's finances.

"For the income approach, what we normally do is we request financial statements from individual businesses, and request income and expenses, so that we can kind of figure out what income we could use to capitalize the value," Haltermon Robinson said.

The year that Mar-a-Lago agreed with the appraiser about its $27 million valuation, Trump and the company listed it as worth $490 million on financial documents given to banks, according to the New York Attorney General.

It's not unusual to tell a bank that a property is worth more than its appraisal by the government, but the difference is rarely so vast, said Beracha. 

"Usually when you speak to two well-informed parties, you do not see gaps like this in valuation," Beracha said. "If we're both experts, if we both know what we're doing, we're going to value that usually within a 10, 15, maybe 20% differential of each other, but not by thousands of percentages."

Still, Beracha said, "When I teach real estate, we never look at county appraisals as reliable guidance for what the property's worth. We always do a market analysis."

Beracha said there are a couple factors that appraisers don't consider that lead them to undervalue a property like Mar-a-Lago, which Trump purchased in 1985.

"The more unique the property is and the longer it is owned by the current owner, the higher the likelihood that the gap between what it's actually worth and what the county says it's worth is large," Beracha said.

Trump says the gap is extraordinary. The New York attorney general and the judge disagree.

The headline of this story has been updated.

In:
• Donald Trump
• Mar-a-Lago

Graham Kates

Graham Kates is an investigative reporter covering criminal justice, privacy issues and information security for CBS News Digital. Contact Graham at KatesG@cbsnews.com or grahamkates@protonmail.com