There has been a rise in cases of con artists trying to rip-off residents by offering cheap, unsolicited labour - usually laying bitumen or roofing - before making off with the payment without doing the job.
Fair Trading NSW says the increase in reports of scammers posing as tradespeople in the past month has been evident across Lake Macquarie, the Central Coast, Forster and Tamworth.
Commissioner Rose Webb said the so-called bitumen bandits could be extremely convincing, but they exhibited several characteristics that gave them away.
"Members of these groups are nomadic and frequently travel across borders or long distances to seek work so it's very important consumers be on the lookout for them," Ms Webb said.
"Often these persons and groups are from an English or Irish heritage and will present extremely professionally, even with work vehicles and websites.
"They often imply they have leftover materials from a nearby job and offer a cheap price for work carried out that day. They continually adapt their scam, offering Eftpos as they are aware demanding a cash payment can arouse suspicion."
If in doubt, people can verify authenticity using the Service NSW Tradesperson Check tool for free online.
