Police say complaints about trade deals on the internet that have gone bad are on the increase.

The national Electronic Crime Lab says while the internet can be an easy place for con-artists to operate - and  it's difficult to police - there are precautions people can take.
 
A Timaru businesswoman, Dorothy Tucker, has four times paid for goods over the internet and never received them.

"I think they're rotten, they just shouldn't be there, but there are ways for them to sneak in, and they think yeah, I can make a bit of money here," says Tucker.

Unfortunately Tucker is not alone and Timaru police have been inundated with calls from people who have been ripped off.

"I suggest there's been a lot more of this scamming going on, but members of the public don't want to come forward because it's only been a small amount of money, or they're too embarrassed," says Sergeant Hamilton.

The Electronic Crime Lab (ECL) says spending on the net can be a risky business.

"Ninety-nine percent are fine but there's always the potential that things can go wrong," says Maarten Kleintjes from ECL.

People can take precautions like using an intermediary who holds the money until the goods have been received, or using the trader feedback service.

One of the bigger sites - Trademe - runs over a million auctions a month, but says it only hears from police about a handful of transactions that have gone wrong.

"Obviously it's something that's of great concern to us, and the police and us work together to work out ways to deal with it," says spokesman Sam Morgan.