Keito Kobayashi runs a business consultancy out of a condominium in Tokyo, but when he needs to hold a face-to-face meeting with clients he reaches for his smartphone and books a room elsewhere.

Kobayashi, 34, is a frequent user of an online conference-room space-matching service offered by Spacee Inc., one of a number of companies cashing in on the trend for shared offices by tapping into a vast pool of rooms lying idle in the city.

"As our head office is a unit in a condominium, we use a shared office whenever we have a business discussion," Kobayashi said. "When a client wants an emergency meeting, we can readily find an office nearby via smartphone," he said, stressing the convenience of the service provided by Spacee, which operates a network of more than 3,000 shared offices in Japan.

Spacee was founded in 2013 and has concluded contracts with companies to use their idle conference rooms as shared offices. The Tokyo-based firm has developed a system allowing users to book office space online.

No initial membership fee is required for Spacee's services. Charges for office space differ, depending on the location, but mostly range from 540 yen to 1,080 yen per hour. They drop to as low as 108 yen for use in the early morning.

"We have been able to realize inexpensive services by making use of companies' idle assets," said Keisuke Uchida, president of Spacee, which plans to expand its service network to 10,000 shared offices by the end of this year.

Spacee also operates cafes with power outlets and free Wi-Fi targeting free-lance workers, who only pay 50 yen for a cup of coffee.

In a quiet residential area in Tokyo's Arakawa Ward, a shared office opened in January in an abandoned wooden house built more than 60 years ago. It has wireless connectivity throughout, while retaining the original decor and inner garden.

"ivyCafe Neighbor & Work" can be used for 410 yen per day. There is no initial membership fee, and coffee and tea are available free of charge.

Operated by ivyRincs Inc., the space has been well received by users, many of whom are happy with the improved work efficiency they experience in "a peaceful atmosphere unique to a wooden house," said Ko Mizuno, president of the company founded in Tokyo in 2017.

That peaceful atmosphere is also conducive to other activities, Mizuno said, citing a neighborhood book club that rents space for its meetings.