In 2017, Victoria O’Connell rented her London apartment via a home-sharing site to a man who looted and wrecked the place during a party that drew the police. He disappeared, but left her a review on the platform, saying, “Great host.”

The violation convinced her there had to be a more secure way to share homes than dealing with total strangers. Earlier this year, she founded Golightly, an invitation-only platform for women.

“I wanted some kind of accountability, to know the renter as a friend or the friend of a friend,” she said. “I felt I would feel more safe if I had a woman renting.”

Golightly is among several new home-sharing platforms that, in one way or another, aim to improve on the Airbnb or Vrbo models based on who has access to the homes, the kind of units for rent and the fees that hosts pay to list with them.

In the 12 years since Airbnb launched, the home-sharing category has only grown, spinning off niche platforms such as Misterb&b, which targets the L.G.B.T.Q. community, and Noirbnb for Black travelers.

During the pandemic, when Airbnb relaxed its cancellation policies and refunded renters, many hosts sought alternative platforms, which has helped some of the new sites grow. Recognizing the vagaries of travel since the pandemic began, some of these companies are offering flexible cancellation penalties this summer.

But in addition to the challenges any travel company faces in the Covid-19 era, the problem for most start-up, short-term rental platforms is their small size. Travelers will find a limited inventory — perhaps one unit in San Francisco on the new site Zeevou Direct — versus more than 300 on Airbnb, the largest home-sharing site with over seven million accommodations.

“You’re going to always see people who are trying to nip at the heels of Airbnb,” said Joseph DiTomaso, the founder and chief executive of AllTheRooms, a vacation rental search engine and data analytics firm for the industry. “The real question is scale and can these other folks compete with Airbnb and Vrbo on a booking level. Can they drive demand? That’s going to be one of the hardest things to do.”

But for travelers willing to shop around, the following four new platforms offer novel twists on home sharing.

Launched in January, Golightly was just getting out of the starting gate when the pandemic hit, but has grown 30 percent during it, to 590 properties. Most are in the United States and Europe, but there are also homes in Argentina, Israel and South Africa. Prices range from $80 for a mid-century-modern studio in Coronado, Calif., to over $1,000 for a country estate in Ireland.

The trick is gaining access to the offerings. Golightly members, currently at 2,500, must refer any new members in order to preserve the “friend of a friend” network (unaffiliated women can apply for membership and be vetted by a Golightly staffer, who becomes their referring friend). Spanning property hosts, managers and travelers, all members identify as women, including trans women, though they may travel with companions of any gender. The one-time membership fee, currently suspended during the pandemic, is $100.

The vetting process for listings includes an actual or a virtual walk-through by Golightly staffers to verify the homes are as described or photographed.

Members say the private system with traceable connections to other women gives them a sense of security.

“As a woman, with wages not being equal, I think it’s cool we can make a concerted effort for a woman to profit off our business and build a network of people like us who want to make women feel safe when traveling,” said Maura Cusick, a Golightly member who rents her home in New Orleans on the platform.

Hosts can choose from an extremely flexible policy (no penalty the day before) to a restrictive one (a 50 percent penalty one month out).

Time-share owners buy access to a property — typically a two-bedroom resort condo — for a week or more annually.

According to the American Resort Development Association, which represents the vacation ownership and resort development industries, there are more than 1,500 time shares in the United States and over 5,300 worldwide.

The new service Koala, which is scheduled to launch in August, aims to help time-share owners sell their vacation weeks.

According to Mike Kennedy, a co-founder, Koala is positioned as a generational transfer, from an older owner — though A.R.D.A. said the average owner is 44 years old — to a younger traveler, particularly millennial families looking for multiple bedrooms and residential amenities like kitchens and laundry appliances.

Because the units are in resorts — many operated by brands like Hilton or Marriott — time shares may offer some cleanliness assurances in the Covid-19 age that many short-term rentals don’t.

“There’s an added level of trust you get with a hotel, but you get the space of an Airbnb,” Mr. Kennedy said.

He added that because time-share owners set their own rates, and are often looking to break even on expenses, the resale rates for time-share units compared to rooms offered by the resort may be lower. The average price of a two-bedroom rental on Koala, he said, is about $2,500 a week. Owners choose their cancellation terms, ranging from fully refundable 72 hours in advance to nonrefundable after booking.

The new platform MyPlace imagines a world where you don’t seek to make money off your spare bedroom or vacation home. Instead, you’re able to share it only with a trusted circle of friends and family and perhaps their friends and family. Any rental fees would be charged accordingly, such as free to Mom and Dad or having a friend of your college roommate proportionately cover your rent.

Zach Bell and Rameet Chawla launched MyPlace in March just within their own circles, about 2,500 people, with listings in Australia, Costa Rica, Mexico and Spain as well as the United States.

“We’re not creating a public market of B&B entrepreneurs,” Mr. Bell said. “Everyone wants to share, but not rent on the public market.”

Relying on known users, even with a few degrees of separation, aims to build trust into the stay and replaces group exchanges — which the pair say are common on Facebook — with better booking technology.

Travelers would have to be in Mr. Bell’s and Mr. Chawla’s group to have access to their listings. The plan is to make MyPlace available to other groups who can then operate their own private exchange open only to their members when the technology is fully launched later this year.

“Airbnb is an incredible tool for people who want to monetize their assets,” said Mr. Chawla. “We’re aiming outside of that market. With my apartment in New York, my goal is not to make money but I’m paying for it and I’d love to allow friends and friends of friends to stay there.”

About three years ago, as a property manager then living in England, Na’im Payman decided to develop his own booking platform to supplement listings on others. Direct bookings allow him to keep more of the rental rate and to maintain more control, such as setting cancellation policies from nonrefundable 24 hours after booking to flexible up to the day of check-in.

That software, Zeevou, begot Zeevou Direct, a short-term rental service that lists his 260-plus properties and is open to other hosts to list their rentals for free. The site currently lists more than 700 units.

“I’m trying to democratize the hosting marketplace,” said Mr. Payman, who launched the service in March and said he picked up some listings from disgruntled Airbnb hosts. “Building a network of hosts globally without a massive marketing budget means you can get better rates because there’s no intermediary.”

While most properties listed on the site are in Britain, there are sprinklings in Mexico, the United States and Asia, including a trendy loft in downtown Montgomery, Ala. (from $120), a two-bedroom cottage in Napa, Calif. (from $305), and a yurt in Mongolia (from $120).

As for the properties he manages, he still uses other listing services as only 60 percent of his bookings come direct. With no marketing budget to promote the free service, growth of Zeevou Direct has been based on word of mouth.

“We don’t manage bookings, but give hosts the tools to do it themselves,” he said. “We’re trying to redistribute the power back to the hosts to run their business where everyone in the community is respected.”

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