They are the new kids on the block when it comes to floor plans.
Called triple-key apartments, their main attraction is that they have three bedrooms, each with an attached bathroom. This allows the owner to rent one apartment conveniently to three different tenants.
Freehold condominium Liv on Wilkie is offering these apartments, which should attract buyers who want to maximise rental returns from a single apartment.
But there is a catch.
In principle, triple-key units should have three separate entrances with their own keys.
But the ones at Liv on Wilkie have only two entrances.
Located at the upmarket District 9, just a short walk from Dhoby Ghaut MRT, the 81-unit development also consists of one- and two- bedroom units.
Property experts approached by The New Paper think that the "triple-key" concept is a new marketing tactic.
Mr Colin Tan, director of research and consultancy at Suntec Real Estate, said: "Dual-key means separate access and complete privacy as the different tenants would not meet each other. In reality, it's not always like that for some dual-key developments.
"But this (triple-key concept) would definitely arouse interest because people are interested in making money."
According to online promotional material, the dual- and triple-key units at Liv on Wilkie are targeted at "astute investors" and a "key to optimising investment returns".
The developers of Liv on Wilkie, Roxy-Pacific Holdings, declined to comment.
They were the same developers for Liv on Sophia, where all 64 units were two-bedroom, dual-key flats. It was launched last May.