NSW Private car purchase, owner didn’t disclose finance

[Unclem8720]

Hi all. I purchased a car for cash. The sale was a bit rushed in my opinion. Found out a few days later car was under finance. Asked the seller he said it was being paid. Contacted finance company, they only said they want car back and can’t get in touch with original owner. I returned the car to seller twice (which he refused to take back so parked it outside his driveway) and finance company took it from his house. I’ve started a case to get my money back as he hasn’t provided goods equitable to the value of consideration he received. What else could I add? His lawyer wants to lodge a counter claim which is interesting.