Short-term rental companies, Airbnb included, are locking horns with a coalition of advocates over legislation that would regulate those companies’ activities in the District. Both sides are lobbying local lawmakers and rallying supporters in advance of a D.C. Council hearing on the proposal set for Wednesday.

The hearing will likely last for hours, with dozens of witnesses expected to speak about the legislation. It comes as housing costs in the city continue to rise, a situation which some activists claim Airbnb and its peers are exacerbating by removing long-term housing from the market. But those companies and their backers, including hosts and businesses, say short-term rentals aren’t to blame. They say home-sharing benefits the District’s economy, and that over-regulating the practice could damage their bottom lines.

This debate follows similar ones that have played out across the country, leading in some cases to legal fights. Big cities like New York and San Francisco have significantly cracked down on short-term rentals, while other jurisdictions, like nearby Arlington County, have regulated them less stringently. Airbnb launched in D.C. in 2009 and has lambasted the proposed regulations as “unworkable.” But a hotel-union-backed campaign called ShareBetter has endorsed them and exposed a few questionable rentals.

The bill, which Ward 5 Councilmember Kenyan McDuffie proposed in January, would require hosts to register their listings with the city and would limit the number and duration of rental bookings for a given unit of housing. It would also set a 15-day annual cap on what it calls “vacation rentals” (those where hosts do not remain on site overnight), procedures for city inspectors to review listings, and fines of up to $7,000 for hosts who violate the measure’s provisions.

Today, ShareBetter is debuting its latest advertising push against Airbnb with a six-figure digital and TV campaign anchored by a video that paints the picture of “more and more homes [being] used for tourist rentals” and contains the “Neighborhoods for Neighbors” slogan that’s appeared in past advertisements. The group’s representatives say they have amassed thousands of signatures in support of the proposal.

Airbnb criticized the video in a statement. “This ad is another example of ShareBetter and the Working Families Party doing the bidding of the hotel industry—attacking middle-class families who home-share to make ends meet, and travelers who depend on home-sharing to visit communities which lack hotels like those east of the Anacostia River,” the company said.

ShareBetter has won favor with local progressive groups, including the Working Families Party and D.C. Jobs With Justice. These groups all have concerns about low-income residents’ ability to keep living in the city. “District residents are being priced out of their homes by Airbnb and their army of commercial operators who see nothing but dollar signs in their eyes,” says Rev. H. Lionel Edmonds of Mount Lebanon Baptist Church, which is located in Truxton Circle. Edmonds is a member of the D.C. ShareBetter campaign.

Even architects have come out in favor of the bill. “If property owners intend to use their property as a business, then they need to run it like a business, and provide the same licenses and requirements that other property owners are required to provide,” the District’s chapter of the American Institute of Architects wrote in a letter to the D.C. Council last week, citing “similar regulations” in other U.S. cities.

Meanwhile, Airbnb has sent its own “redline” version of the legislation to McDuffie. Last week, in a letter to McDuffie accompanying the redline, which removes the language on “vacation rentals” and suggests lower fines, Airbnb said it “wants to be regulated”—just in a way that is “fair,” “sensible,” and “welcoming” to people. The company has suggested a limit of 180 days per year on short-term rentals—or three times the total number of days that the “typical Airbnb host in D.C. shared their home” in 2016, earning roughly $5,800.

“Rules around home-sharing should be reasonable and not hinder the ability of native and longtime Washingtonians to share their homes a few times a year in order to make ends meet and reinvest in their neighborhoods,” William Burns, Airbnb’s director of public policy, wrote. Like ShareBetter, the company has run its own ads, reports, and press releases, except that these have extolled the platform’s benefits.

McDuffie says he wants to create a regulatory framework for short-term rentals available through Airbnb, VRBO, and their peers. He also says the bill is designed to prevent commercial enterprises from operating unlicensed hotels, thereby reducing the city’s stock of affordable housing—not to obstruct “legitimate home-sharing” by residents hoping for extra income. Yet, the specifics of the bill may change.

“We have received a lot of feedback since introduction on issues ranging from party houses, public health and safety, and the 15-day limit on home-sharing while the homeowner is away from their residence,” McDuffie says in a statement to City Paper. “I am open to revising the bill, including the 15-day number, and I am looking forward to Wednesday’s hearing as a way to hear directly from impacted residents, so that we can find the right balance for the District of Columbia.”

After the scheduled hearing, the legislation could come up for a council committee vote later this year. No other councilmembers co-sponsored the bill when McDuffie introduced it more than two months ago.

This post has been updated with Airbnb’s statement on the ShareBetter ad.