Miss your mother's home-made soup? There's an app where you can "rent a mum" to cook some for you. Need someone to courier a package at 2.30am? Looking for a pet dog for an Instagram project? There are apps for those too.

The sharing economy has moved well beyond ride sharing and renting spare rooms. And that makes perfect sense to Parkson Yip Tak-yin, vice-president of strategic business development at US-listed Sharing Economy International, which launched BuddiGo this month.

BuddiGo's delivery service relies on a network of "buddies" who practically become couriers while commuting. It's basically about trip sharing, Yip says.

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"As an example, the buddy nearby your location has to go to work in [Hong Kong's] Central [business district] and you give him HK$20 [US$2.50] to help you deliver something to, or buy something from, Central," he explains. "The HK$20 can help subsidise his transport cost and save you the trouble of going to Central in person for the errand."

With millions of commuters making journeys across the length and breadth of Hong Kong daily, in Yip's utopian vision of universal sharing everybody can be a paid helper and underutilised manpower put to full use.

He believes the public participation rate would be high, especially among retirees. "They have [not much] to do every day and they enjoy the HK$2 discounted travel fare for elderly citizens. They can make frequent trips, run errands for others, and earn money."

Before working for Sharing Economy International, Yip was managing director of ECrent, one of the largest online sharing platforms in the world. ECrent encourages people to share through renting to protect the environment.

Set up in Hong Kong in 2013, it rents out all sorts of products, from bicycles to popcorn machines, and offers services such as bridal make-up and venue decoration. Among ECrent's more eccentric offerings are mums-for-hire for those single salary earners who yearn for home-made soup.

With around one million users worldwide, ECrent charges US$6 for putting an item up for rent online but nothing for renting it, leaving the two parties to agree terms for the rental.

Not everyone buys into the concept of sharing, though, especially when it is sentient beings that are being shared. ECrent courted controversy in Hong Kong in 2016 when its pets-for-hire service allowed users to try keeping a pet before deciding whether to buy one. This raised the ire of animal welfare activists, who said such services distort the value of life.

Pet-for-hire services are popular in Korea and Japan, however, with young couples renting pets for their holidays and returning them before they go back to work.

Yip says there is public demand for pets-for-hire services. "There are pet product expositions which need animal models. Pets can also be rented for advertising.

"To ensure the welfare of the animals, the owners can be with the pets throughout the rental period. Those who have big attachment to their pets will not allow them to stay overnight in strangers' houses."

A quick search for pets for hire on Xian Yu, a second-hand goods site launched by Taobao, the online retail platform of e-commerce conglomerate Alibaba yielded a couple of listings of pets available for rent as models. Pictures of furry cats holding lipsticks and bottles of perfumes dot Taobao itself. (Alibaba is the owner of the South China Morning Post.)

Beijinger Han Tong recently put up a listing on Xian Yu to rent out her British shorthair and American shorthair cats, and her two poodles, as models. She said renting them out for part-time modelling stints can help cover some of the expenses of keeping them.

"We will be there [with the pets] throughout the process, like for five to six hours a day. We worry about their welfare too. We never think of putting them in a strange environment [without their owners nearby] for a few days," she says.

While pet rentals may raise eyebrows in the animal welfare community, proponents of the practice argue that the concept is just the same as the long-standing practice of household pets serving as therapy animals in the children's wards of hospitals and at old people's homes.

Humans, on the other hand, are harder to share, though there is a plethora of online platforms where you can hire someone to act as a temporary relative or lover.

In Japan, "rental family service" is so popular that it has practically become an industry. A recent New Yorker report on the phenomenon featured a widower who rented two women to act as substitutes for his deceased wife and estranged daughter to give him some comfort for a while.

On the listings menu at Family Romance, one of the agencies in Japan that offers "replacement relatives", slim-looking mothers and wives are available for hire (as overweight women are often considered an embarrassment in Japanese social circles).

In China, single men and women have used online partner rental services in recent years to hire fake spouses in order to stop their parents nagging them about settling down and starting a family. However, Yip says Hong Kong is more conservative than China and not ready to embrace the concept of "hiring" a boyfriend or girlfriend.

"I have lived [in China] for a long time. The common practice of hiring a [platonic] girlfriend is above board. It's to serve a practical purpose, like bringing a partner home to please the parents."

He also says that being able to rent a substitute mother or father can help heal the mental scars of those who come from a broken home. "There are unfortunate children who don't have parents. They never experience the feeling of having a complete family," he says.

Yip thinks Hong Kong should catch up with other parts of the world and embrace an economic future that everyone can benefit from. "With the exception of illegal things like weapons, anything can be for rent."

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