Two men have been arrested and one is facing deportation after allegedly ripping up the driveway of an elderly couple who refused their offers of work.

The NSW Department of Fair Trading says that a 25-year-old UK national and a man from Kosovo approached an elderly couple on Tuesday at their home in Sydney's north and told them their driveway needed resealing.

The couple refused the offer of work and the following day they found their concrete driveway had been reduced to rubble and a pile of debris blocked access to their property.

Fair Trading Commissioner Rod Stowe says the workmen thought they had found a soft target.

"These people were savvy enough to call police but there's been people who have been intimidated and actually paid thousands of dollars," he said.

"[The conmen] are quite charming when they knock on your door and offer you this cut price job but later they can become quite intimidating particularly when it comes to payment".

Fair Trading says the Kosovo national was found to be without a visa and has been sent to Villawood detention centre while the other man is believed to be part of an organised crime group of travelling conmen that targets vulnerable people.