It's all thanks to a stand-off between competing property owners, says Daniel Wong Hon-shing, chief executive of real estate agency Midland IC&I.

"Russell Street is one of the world's premium locations, which influential developers have been eyeing constantly," Wong says. "Some may own a shop on the ground floor, others may have bought units upstairs. There're also individual owners, who are patiently waiting for a sky-high acquisition. But it takes 80 per cent ownership to take over a [multi-level] property ...

"In particular, both Emperor International and Soundwill Holdings want to be the 'property king of Russell Street'."

Both companies have bought units in the two walk-ups, but neither has the upper hand. "As neither needs [to sell] to raise cash, the standstill is bound to continue," Wong says.

This is good news for the tenants, whose small, independent businesses offer welcome alternatives to shoppers fed up with the homogeneity in shopping malls.

Rents for street level shops can cost more than HK$1 million per month, but stepping into the narrow corridor between the Kiehl's and Blancpain shops, at 26-28 Russell Street, leads you to Cafe Corridor, which pays less than HK$150,000.

The cosy coffee shop, which opened in 2001, was the first business to operate from the residential building. Felix Wong Kim-fei, its owner, has seen many ups and downs since then; he still recalls how he had to close the cafe in 2004 when his landlord tripled the rent after the solo travel scheme - launched in 2003 - sparked an influx of mainland visitors.

Over the next three years, Wong kept himself busy as a coffee consultant while the venue was rented by a Korean noodle shop, then a dessert shop and finally a health clinic.

In 2008, he reopened Cafe Corridor in the same space; the rent was still as high, but with more experience Wong was eager to return to where his coffee empire started.

While his top priority is the quality of the coffee - he roasts his own beans and produces four special blends - the warm ambience of the cafe, with wood fittings and a small outdoor area at the back, is also important. "It's a very convenient location," Wong says. "Guests have to walk down a corridor, but if that means paying one-tenth of what the other ground floor shops are paying, I'm fine with it."

It's only a few steps further, and customers love the way that it's quite hidden, he adds. "Everyone comes to chill and have a coffee - we all need a little break. We have built our reputation through word of mouth, so being slightly out of the way is not a problem."

Niche businesses such as sex toy store Wanta and MiNT, a shop selling vintage Polaroid cameras and accessories for enthusiasts, are better off in cheaper, upstairs spaces.

Engineering graduate Gary Ho started MiNT five years ago - two floors up from the cafe. His business has grown from a two-man operation to a team of 20, with a back office in Kwun Tong.

He is delighted with the shop's location as his customers - including many celebrities - love the isolation and the sense of being "in the know".

"Several flights of stairs are nothing to Hongkongers - there are stairs everywhere anyway," he says. "I prefer that to being on the ground floor on a street which nobody has heard of. It's ideal for us also because those who walk up are customers looking for our products, instead of walk-in visitors who take up time with random questions."

MiNT also sells through its website and at 50 other outlets, mainly in the Asia-Pacific.

"Foreigners are impressed when we say our showroom is right next to Times Square. They seldom visit but if they do, most are pleasantly surprised."

Ho also enjoys the camaraderie built up between the people running businesses in the building; everybody is friendly. Ho and his staff love the coffee from Cafe Corridor, and help to redirect customers to Wanta if they wander in by accident.

"People are a lot more open about sex now and most of our products have very modern designs," says Wanta founder Chris Lee Kin-wai before biting into a piece of cheese cake from the cafe. "But it's always good to offer more privacy to customers who may feel embarrassed."

Wanta started in 2000 as an online store selling condoms and opened as a small shop in the Russell Street site five years later. In 2012, it expanded upstairs in a larger unit as its range of products expanded - recent additions include various whips and handcuffs - tapping into the global popularity of the erotic novel,

Rents rose this year even as business slowed, so Lee installed an LED screen on an exterior wall to promote his products. He says: "It's important for a retail shop to have an attractive display, but that's reflected in the rent. The LED screen is a great alternative for an upstairs shop like ours."

Indeed, an exterior wall offers valuable advertising space and Lee counts himself lucky to have one for his use.

Wong, of Midland IC&I, says: "International brands usually open at prime areas as window displays and sales are not a big concern; it's for marketing. Many are targeting the mainland market. Their concept of brand names is simple: they must be from overseas and seen on a well-known street. Mainland shoppers feel confident about brands they see on Canton Road and Russell Street.

"Shops may lose some money because of the rent in Hong Kong, but soon earn it back when opening shops on the mainland, where rents are cheap. Besides, several million dollars isn't much to spend compared with costs of TV commercials and the like."

At 18 Russell Street, People's Coffee & Books gave up its exterior window - now used for advertising by other retailers - so that it could stay in the second-floor unit it has used since 2002.

Luxury watch brand Longines planned to open its flagship store by taking over the bookshop unit and a street-level shop; but it abandoned the idea as it was too difficult to build an internal staircase linking them.

However, the bookshop still faced having to pay twice as much for the rent until director Paul Tang Tsz-keung reached a settlement with the property owner.

"All we had to do was sacrifice our window display for the watch brand's adverts," he says. "We were more than happy to and got to stay for the same rent, too."

Another watch brand, Jaeger LeCoultre, is now in the ground-floor unit, but Tang's business has remained stable.

The bookshop was quick to cater to the growing mainland clientele, with a range of publications in simplified Chinese. After others jumped on the bandwagon, Tang resumed stocking books in traditional characters, but with a focus on titles that are banned in China, including those on religion, sexuality, and feng shui.

"Loyal customers return for our political books on June 4, Tibet, Xinjiang and so on, which are scarce elsewhere - even in Hong Kong," he says. "Our customers - reporters and academics - have money and don't care about discounts. All they care about is whether they can find the titles they want.

"We've become more specialised because the scene is changing. I can't change who comes to Russell Street, but we can change our products and services to meet demand."

People's Coffee & Books has even started selling formula milk, in addition to souvenirs and supplements. He says it may not be a good image for a bookshop, but it is the way many such shops are heading now.

While Tang is busy exploring digital platforms for the long-term survival of his bookshop, steady online sales are giving the owners of both MiNT and Wanta a sense of optimism about prospects for their businesses.

All the shop owners have grown attached to the tong lau where they launched their businesses and hate the idea of seeing the building pulled down.

However, like Wong, of Cafe Corridor, most are prepared for the day when redevelopment will force their departure. .

"I'm not worried because there's nothing I can do about it," Wong says. "It's just like asking me if I'm worried about death when it's inevitable. If they want to redevelop this building, I can't stop them. It's only a matter of when."