Wanted fugitive Ruja Ignatova hasn't been seen since October 2017.
A recent property listing hints that Ignatova is alive and still on the run, reports say.
Bulgarian-born Ignatova, 42, is wanted by the FBI for allegedly scamming investors out of $4 billion between 2014 and 2016 in a Ponzi scheme using her now-defunct company OneCoin.
In October 2017, she vanished until documents related to a penthouse apartment in London seemingly pointed to her whereabouts, the New York Post reported.
"It suggests she is still alive, and there are documents out there somewhere which contain vital clues as to her recent whereabouts," Bartlett said.