It's hard to find people here who are neutral about Airbnb, the explosively successful tech firm that has disrupted more than just the hotel business.
Judith Davis, 71, loves the short-term rental platform. A quintessential San Franciscan, Davis was married to the man who discovered Janis Joplin. She owns a memorabilia-filled Queen Anne Victorian in Noe Valley. She says she cannot make ends meet, let alone keep up with home repairs, on her $965 monthly Social Security check.
For five years, she has rented out the lower level of her home on Airbnb for $125 a night, earning a whole lot more than when she had a full-time tenant. If the city enacts a proposed limit on the number of nights she can rent out her house, she said, "I will lose half my income. And it wasn't that much to begin with."
Two miles away, in West Portal, Libby Noronha, a 66-year-old federal government retiree, told me she is not a fan of Airbnb. Noronha bought her traditional two-story detached stucco home in 2012, on what she believed to be a quiet residential street.
She soon learned that her next-door neighbor, a computer engineer, advertised three rooms of his house on Airbnb. She might not have minded, except the entrance to two of the units is a side door located in the 70-inch-wide passage between their homes.
"He has as many as six people coming and going, virtually all the time," she said. "There's luggage rolling on concrete. My dog is barking at 2 in the morning. It drives me nuts, frankly."
Nor is she sympathetic to people like Davis, who have become the face of Airbnb's campaign to fend off regulation.
"The entire argument for Airbnb is the whining: 'Oh, I can't afford to stay here if I don't rent out my rooms,'" she said. "What were these people doing before Airbnb?"
A handful of California cities have begun to address the "hotelization" of their residential neighborhoods. But in San Francisco, which has been transformed by the tech industry, the battle seems more pitched.
"This is round whatever in the long-standing fight in San Francisco over housing and development," said Roger Ritter, president of a homeowners group on the city's west side that wants short-term rentals more tightly regulated. "We see this as an assault on zoning laws."
Last month, Santa Monica dealt a big blow to short-term rental companies when it imposed a tough law that allows only homeowners who reside on the premises to rent rooms after registering with the city. The city will also collect a 14% occupancy tax.
San Francisco had already implemented a similar scheme. Unfortunately, fewer than 300 out of an estimated 6,000 short-term landlords registered.
No one knows how many tenants have been displaced by landlords looking for bigger returns with short-term rentals. But stories like Susan Whetzel's are not rare. Whetzel, 43, was tossed out of her beloved flat next to Mission Dolores Park by a landlord who now rents it on Airbnb.
"He charges $250 a night for my place," she told me over coffee. "The house is now a three-story hotel."
The city's budget and legislative analyst has estimated that between one quarter and one half of the rentals on sites like Airbnb are owned by landlords who do not live on the premises, "commercial hosts" who operate illegally.
"We could be more accurate if Airbnb gave us their data," said Supervisor David Campos. The company has refused, citing privacy concerns.
Pro-tenant groups scoff at that.
"I'm sorry, but I don't believe a $20-billion tech company is really concerned about users' privacy," said Sara Shortt, executive director of the Housing Rights Committee of San Francisco. "That's generally not been a big concern of theirs."
She believes that Airbnb, which charges hosts 3% and charges guests 6% to 12%, is simply protecting its income.
"In what other world," she asked, "would you be perfectly aware that you are facilitating illegal activity by providing the tools to do it and not take measures to filter out those who are violating the law?"
I want to like Airbnb.
It provides a very cool service. The people who work there seem nice. When I visited the South of Market headquarters, spokesman Christopher Nulty gave me a fresh-baked vegan oatmeal cookie, which was delicious.
But my conversation with David Owen, the company's regional head of public policy, was less satisfying. I wanted to know why the company is so resistant to regulation and to weeding out illegal rentals.
"I think there are a lot of rational conversations to have about what are the real issues that we're concerned about, and what are the best solutions to address them in our context and in other contexts," Owen said.
When I asked about regulation, he said: "We engage with elected officials everywhere to help educate them about what's going on and to help present our view of what's happening, what good regulation looks like and what bad regulation looks like."
So I pressed on about what "good regulation" looks like.
"Optimal regulation," he said, "is one that takes into account the concerns of our community and the folks that are doing this and, you know, balances them against the unique issues that are confronting that city."
The unique issue confronting San Francisco, of course, is a lack of rental stock, possibly exacerbated by commercial hosts who break the law with Airbnb's tacit approval.
"If a city's mechanism for enforcing the law is requiring an Internet company to do X, Y and Z," Owen said, "then that law is simply not going to work."
We'll see. Sacramento lawmakers are weighing a bill that would require short-term rental platforms to report booking information.
ShareBetter SF, a coalition of tenants, unions and homeowners, is trying to get a tough measure on the November ballot that would cap all such rentals at 75 nights a year, require companies and hosts to produce quarterly reports, and fine companies for listing rentals that don't comply with the law.
Now that would be a serious disruption. For Airbnb, anyway.