NAPA -- The Napa County Board of Supervisors recently heard arguments for changing the strict ban on vacation rentals in unincorporated portions of the county, which would include the agriculture preserve.

Scores of residents and business owners in favor of easing the restrictions lobbied the board to allow more flexibility in renting out vacation homes, arguing that such rentals could add significantly to the local economy and that many are currently functioning illegally, thus operating outside the financial oversight of the county, according to video footage and meeting minutes on the Napa County board’s Web site.

The board voted in December to prohibit vacation rentals but decided after public response to wait until June to implement any permanent ordinance.

Liza Graves, co-founder and chief operating officer of the villa rental company Beautiful Places, told the board that approximately 300 illegal vacation rentals are currently in operation, and they generate between $45 million to $57 million a year throughout the county.

Accordingly, she said, the county’s hotel tax revenue could increase by up to $1.45 million if such rentals were permitted.

But any change to the existing ordinance could face a legal challenge by way of Measure J, a law passed in 1990 meant to limit growth, according to county attorney Minh Tran.

Measure J, which was extended by Measure P in 2008, requires that any proposed change in zoning on the agricultural preserve be put to a public vote, meaning property owners in unincorporated parts of the county would need public approval before renting out their private homes or properties.

Supervisors will take up the debate again on April 22, when planners and attorneys for the county will present a legal analysis.