Police are hunting a man suspected of scamming businesses by claiming he has a machine that can print real money and offering to buy the premises.

Detectives believe he has approached at 10 businesses in the Logan area south of Brisbane and made off with $20,000.

Police said he visited a kebab shop in Browns Plains on March 9 and told the owner he had a machine that could duplicate legitimate currency.

After corresponding with the owner a number of times, the man took a safe and black wooden box with a power cord to the shop on March 25.

Police said he put two bundles of what he said was $100,000 cash in the box, then asked the owner to put in $50,000 to be duplicated.

When the owner refused, the man became angry and put the purported $100,000 in the safe and said he would return the next day.

The owner later forced open the safe to find photocopies of cash. No money was stolen.

The man allegedly went to a Slacks Creek business between March 11 and 26 and made the same offer to the owner.

The owner withdrew $20,000 and gave it to the man, who ran the money through a black box with a power cord, along with what looked like cash he had brought himself.

"The box made a humming noise as this occurred," police said in a statement.

"After the process finished, the man put the two bundles of money into a safe, and the man said he would return the next day with the key so they could open the safe together."

When the man did not arrive, the owner forced open the safe to find two bundles of phoney notes, police said.

Police have released security video of a man they want to speak to, and are urging anyone with information to come forward.