The Seattle City Council has released a new set of regulations designed to prevent property owners from operating Airbnbs and other short-term rentals as if they were hotels — part of a larger effort to ensure an adequate supply of long-term rental stock for the city’s permanent residents.

The new rules would limit hosts to two dwelling units each, require them to obtain special licenses, and levy a $10 per night tax on Seattleites operating short-term rentals. The tax would be levied starting Oct. 1, 2018, and the rest of the regulations would take effect 30 days after they are signed by the mayor, whomever that ends up being. The regulations also require short-term rental platforms — like Airbnb, HomeAway, and VRBO — to obtain a special “platform license” to facilitate bookings in Seattle.

Anyone who rents property on a site like Airbnb will be required to obtain a short-term rental operator’s license, which costs $75 a year. Hosts who violate any of the new regulations could be fined $500 a day, for up to 10 days or until they comply. After the 10-day period, the fine jumps to $1,000 per day.

Airbnb hosts are already required to have a business license and will still need one on top of the short-term rental operator’s license. A separate ordinance clarifies which regulations will apply to traditional bed and breakfasts, provides an official definition for “short-term rental,” and adjusts land use rules for those types of dwellings.

The funds raised from short-term rental taxes and fees “are intended to support investments in affordable housing and to support community-initiated equitable development projects,” according to the proposal.

The regulations were introduced by Councilmember Tim Burgess and co-sponsored by Councilmember Rob Johnson. The new ordinances are the latest in a series of controversial proposals, designed to curb the spread of short-term rentals in Seattle. The city is mired in a housing affordability crisis, driven by an influx of newcomers, many of whom have been drawn to Seattle by the promise of high-paying tech jobs.

Airbnb has been working with the city to come up with a set of regulations that let homeowners earn extra cash by renting out their properties on a short-term basis, while keeping as much long-term rental stock on the housing market as possible.

“Airbnb helps Seattle families earn extra money to afford to stay in their homes while bringing visitor spending to local businesses outside of typical tourist areas,” Laura Spanjian, Airbnb’s Northwest public policy director, told GeekWire in an email. “We are glad the proposed regulations will allow our hosts to continue sharing their homes and making important economic contributions to the city. We hope to continue working with the City of Seattle to create a streamlined registration system that makes it easy for hosts to get a license and protects long-term housing stock.”

Councilmember Burgess did not immediately respond to GeekWire’s requests for comment.

The new regulations would require platforms like Airbnb to collect license numbers from hosts in Seattle before providing booking and listing services. Those companies will also have to remove non-compliant listings if Seattle asks them to. Airbnb, VRBO and similar services will have to provide quarterly reports to the city on the total number of properties listed on their platforms and the total number of nights that were booked. Those companies will also be required to pay a yet-to-be-determined quarterly fee based on the number of nights booked.

Some Airbnb hosts will be exempt from the two-unit maximum mandated by the regulations. Hosts already operating a short-term rental in the Downtown, Uptown, and South Lake Union neighborhoods before Sept. 30, 2017, will be allowed to rent up to two additional dwellings on a short-term basis, for a total of four. That same exception will also be available to hosts in First Hill and Capitol Hill if they have been operating a short-term rental before Sept. 30 in a multifamily building constructed after 2012 that has five or fewer units.

Dwellings that are operated by a government entity or charitable organization that provide temporary housing to people receiving medical treatment are not subject to the regulations.

The new set of rules are currently in committee. Friday the Council is holding a special meeting of the Affordable Housing, Neighborhoods & Finance Committee, where the short-term rental regulations will likely be discussed and voted on.

The new regulations were first spotted by Seattle City Council news sight SCC Insight.