The city of Portland is close to finalizing a data-sharing agreement with Airbnb the official in charge of negotiations said Monday, months after auditors blamed the lack of data for the city’s trouble regulating short-term rentals.

Auditors indicated in July that reaching such an agreement is key to ensuring all Airbnb rentals comply with city permitting rules and pay all lodging taxes owed. Data access would also bolster enforcement of rules stating short-term rental hosts must be the primary resident of their listing and keep guest stays to a maximum of 30 days.

The last time auditors checked, they found four in five listings do not have required permits and tax collectors cannot accurately audit revenues, according to the the July report. Lax enforcement allows scofflaw listings, such as unpermitted rentals or hosts with multiple hotel-style listings, to flourish, auditors found. That practice may exacerbate Portland’s supply-stressed housing market.

Officials hope to reach a deal with Airbnb in January, Thomas Lannom, director of the city Revenue Division, said Monday. “It’s taking longer than either side wants, but still moving forward,” Lannom said.

Negotiators have already agreed on provisions that will allow the city to collect Airbnb data on listings and hosts, Lannom said. But technical details remain to be resolved, he said.

Airbnb spokeswoman Laura Rillos said in a statement that Portland’s listings registration system is “onerous” and “difficult for many hosts to navigate.”

“We remain committed to working with the city on a simplified registration system that that will make it easier for hosts to register and for the city to enforce its laws,” the statement said.

Kari Guy, audits director in the city Auditor’s Office, said officials should continue their push to get Airbnb data. If the agreement falls through, Guy said, officials should use publicly available data, such as information available on the Airbnb website, to better regulate short-term rentals.

-- Gordon R. Friedman

GFriedman@Oregonian.com