The issue is it is very hard to know the item sold by market place in amazon is genuine sale.
I lost around 20nz due to I paid a samsung evo 850 500gb ssd for usd 140(the normal price from amazon prime was around usd156) and the seller is doing a scam and never ship the item. The amazon refund my money same amount in usd to my credit card. But nzd was frustrated quite a lot in that month and I ended up lost 20nz from my credit card account due to currency without purchasing anything.