More people are complaining to authorities after buying vehicles online and unseen - only to find they are not what is advertised or there are serious faults with them.
A warning is contained in a disputes tribunal report to the Government which cites several examples, including the case of a couple who bought a vehicle for almost $20,000. They say they haven't been able to drive the car, which had several faults.
In that case the tribunal found the car had been misrepresented, but the decision is now being appealed and is before the courts.
The purchasers have told the Herald they would think twice before ever buying "sight unseen", and a consumer advocate agrees such deals are just "asking for trouble".
In his annual report, the adjudicator of the Motor Vehicle Disputes Tribunal, Christopher Cornwell, said the tribunal was hearing more claims from buyers who had purchased vehicles on Trade Me without even seeing them.
"In most of these cases the consumer compounds the folly of buying sight unseen by failing to get an independent pre-purchase inspection of the vehicle carried out," Mr Cornwell said.
Purchasers who trusted the accuracy of descriptions and photographs put on Trade Me often came to the tribunal claiming the vehicle's condition was misrepresented to them by the seller, he said.
"When these purchasers buy, as is often the case, by auction, they have no recourse against the trader for mechanical or other defects under the Consumer Guarantees Act."
Consumer NZ said its advice was to always get a car inspected. "It's sensible, even if you know a lot about cars," said research and testing manager Hamish Wilson. "Often a second opinion picks up things you wouldn't have picked. It just seems to us buying something sight unseen is really asking for trouble."
Mr Wilson said Consumer NZ was sometimes approached by people with cars that had problems after they purchased them from what they called "reputable firms", and thought "they could trust them".
"Our answer is no ... As soon as you make that assumption you're probably going to end up in trouble. Our advice is if you're going to buy a second-hand car you need to satisfy yourself that it's a decent car and do the necessary checks."
Mr Cornwell said it was preferable to get an inspection by the Automobile Association or a mechanic appointed by the purchaser - not someone arranged by the trader.
A Trade Me spokesman said it was no surprise more issues were occurring as more people used online shopping, but they needed to do their due diligence.
"Every listing on Trade Me Motors has a checklist for car buyers displayed which includes links to getting a car inspection and checking the vehicle's ownership history.
"On the bottom of every car listing there is also a sheriff badge which allows people to connect with our ... policing team immediately if they have any concerns around a listing."
* Ask questions and check out the seller's Trade Me feedback. And if you're buying from a dealer, make sure you ask to see the Consumer Information Notice.
* Questions to ask the seller: How long have you owned the car? Why are you selling the car? What is the car's service history? Do you have the receipts for the work? Has the car been in any major accidents?
* If you think the car looks good and drives well, get a mechanical and background check done by a professional.