Police are warning of a new scam going on Facebook Marketplace that's seen dozens of people in New Zealand swindled out of their cars.

The scam has become so common across Auckland in particular that fifty complaints have been made to police and nine people have been charged.

Police and consumer groups are warning people to be careful buying and selling on Facebook Marketplace, which is largely unregulated

Jessica Wilson, head of research at Consumer, told Heather du Plessis-Allan that the scam involves old chequebook being used to make payment. 

"They deposit the cheque in the person's account, so the person thinks the money is there. The transaction takes place, the car is handed over, and a couple of days later, the cheque bounces."

The advice is to make sure that the funds are cleared before the item is handed over. 

Outside of car trades, Wilson warns that the onus is on the person selling or buying when it comes to using Facebook Marketplace. 

"There's not really any protection there."

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