BUYING a second-hand phone online could be a risky practice for consumers with three quarters of devices not being worth what is paid for them, new research from O2 claims.

The mobile operator and consumer affairs expert Dominic Littlewood bought 52 phones from a range of classified and auction websites and claimed that 66% had been falsely advertised in some way.

More than a third (34%) of the phones bought were also classed as being broken and more than half were not in a good enough condition to be sold when compared to those in O2's own refurbished phone scheme.

The research also claimed that 12% of the phones bought had broken screens with another 12% having cameras or buttons that did not work.

Mr Littlewood, who has hosted consumer awareness show Cowboy Builders, said: "If you smell a rat, you're probably dealing with one. Not only were a lot of the phones I looked at fake, or broken, some didn't even turn up.

"If you're buying a second hand phone, you are far better buying from a trusted operator where you can get a guarantee, rather than a stranger off the internet.

"You wouldn't buy a phone from Del Boy, would you?"

According to the study, only one in four of the phones bought online would pass O2's "Like New" test, which analyses a phone's battery, audio, screen, interface and connectivity before restoring and reselling it at a reduced price.

Other phone manufacturers also offer similar trade-in or refurbishment services to customers.