South Australians are being urged to be on the lookout for so-called bitumen bandits, targeting parts of suburban Adelaide and the hills.
Commissioner for Consumer Affairs Dini Soulio said the itinerant tradies often go door to door, claiming to have some leftover bitumen from roadworks, and offering to work on a consumer's driveway for a reduced price.
"These people aren't licensed, and the work they do is always of a poor standard," Mr Soulio said.
"In recent days, we have received reports of sightings in Ferryden Park, Unley, Mount Compass and Windsor Gardens.
"We have also been advised that they may be advertising around Verdun."
Mr Soulio urged consumers to be on the lookout, and exercise extreme caution when dealing with unsolicited offers for bitumen work.
"Just remember, the cheapest offer usually won't be the best - which is why you should never accept an unsolicited offer to do bitumen work without shopping around," Mr Soulio said.
"Get quotes, look for testimonials and get references from friends and families who have had similar work done.
"And never get work done without checking that someone is licensed to do the job - and, if you have any doubts, check the CBS public register."
Mr Soulio said that reports in recent days have involved the loss of at least $5000 by consumers, with the tradies targeting homes, small businesses and commercial sites.
If you have concerns about an approach from a tradesperson, contact CBS on 131 882.
To check whether a tradesman is licensed, you can also check the public register on the CBS website.