From another forum, a poster said this when asked where did he get that figure:
(The judge didn’t determine the value was $18 Million.
The Palm Beach County Assessor set the valuation at $18 Million IN 2011 and it had grown to $27.6 Million in 2021.)
https://www.usmessageboard.com/attachments/1695847835832-png.834981/
Well if the palm beach county assessor came up with then it is a legit source. Leftist and biased perhaps but they have the responsibility.
One would need to see if this $18M figure for 2011 is consistent with other similar properties if they even exist in this area.
As you said the valuation is not a current valuation but a valuation for 2011.