The long-running case involves the Sosnovka-1 dacha to the west of Moscow, which a government property watchdog claims was bought by Kasyanov illegally, and should be returned to federal ownership.
A court official said the examinations have been ordered because the agency has failed to produce any documents justifying the level of compensation sought.
The plaintiff is seeking some $4.1 million in damages for the 11.5-hectare luxury property, which it claims was acquired at a knockdown price through a fake auction set up by Kasyanov while he was still in office.
In February 2006, the Moscow Arbitration Court deemed the auction illegal, but stopped short of seizing the property, ruling that the ex-premier had bought it in good faith.
President Vladimir Putin's first premier in 2000-2004, Kasyanov is now the leader of the opposition Russian People's Democratic Union, and he has repeatedly accused the Kremlin of clamping down on civil and political liberties.