Vacation rental operators on O'ahu are getting around a 30-day minimum renting period by signing fraudulent contracts to deceive city investigators, a community group has charged.

The rental operators frequently use contracts that cover a 30-day period, even when guests stay for just a matter of days, said Don Bremner, spokesman for Keep It Kailua, a group that opposes vacation rentals and bed-and-breakfast operations in city neighborhoods.

"They advertise for 30 days or more, but we've obtained several contracts that show people are staying for shorter periods and paying a daily rate," Bremner said.

Some of the contracts were obtained by people posing as prospective tourists wanting to stay in neighborhood homes for short periods, he said.

In the past, city investigators have tried to enforce the 30-day minimum requirement by going after rental operators who advertised daily rates for their units. Now, because of enforcement efforts sparked by those advertisements, the operators have changed tactics, Bremner said.

"The intent is to deceive the city investigators," he said. "It gives the enforcers a bigger problem to deal with."

City Planning Director Henry Eng said the city is investigating the new practice.

"Yes, this appears to be a new strategy and it has been brought to our attention," Eng said. "We are conferring with our corporation counsel to determine how to handle the situation."

Earlier this month, city officials announced new proposed regulations designed, in part, to increase the number of legal bed-and-breakfast operations in neighborhoods while imposing new requirements for operations. The regulations, however, do not largely affect temporary vacation rentals, which are short-term leases of vacant homes and apartments.

The first public hearing on the proposed regulations is set for Nov. 28 before the city planning commission.

Bremner said his group would turn evidence of the fraudulent contracts to city and state law enforcement agencies for possible action.

"We are continuing to respond to requests for investigation on illegal short-term rentals," Eng said.