Sophie Monk is an expensive crash victim -- TMZ has learned, the model's demanding at least $900,000 from a driver she claims temporarily put her in a wheelchair after a 2010 car accident.
TMZ broke the story ... Sophie sued driver Delvinder Sing Bains back in April, claiming the guy caused her severe injuries when his Ford Explorer collided with the Prius she was riding in.
Sophie was seen being rolled around in a wheelchair soon after the accident -- and according to the lawsuit, the crash cost her a fortune in medical bills.
Now, she's putting a number on her damages -- at least $900,000, plus loss of earnings, costs of suit, medical bills, and more.
Attempts to reach the driver she's suing were unsuccessful.