(The apartment at the top of GuocoLand's project has a pool, cabana, entertainment area, jacuzzi and panoramic views of the CBD, Marina Bay and Sentosa.)

Penthouses usually fetch higher prices due to their covetable expansive space, scenic views or indulgent amenities. This luxurious penthouse has all three, and is also the highest residence in Singapore. Supposedly priced at S$108 million, the super penthouse at Wallich residence is due to be released by Gucoland later this year.

While the 21,108 square foot triplex is the highest residence in Singapore – the 64-storey tower in which Wallich Residence is located is 290 metres high – it turns out there may be at least one other penthouse still in the hands of its developer which has an even higher price tag.

According to the grapevine, SC Global Developments has a S$128 million indicative price for the 17,500 sq ft super penthouse occupying the top three levels – 23, 24 and 25 – in the Signature Tower of The Marq on Paterson Hill, although when approached, SC Global said that the unit is not for sale.

The exclusive unit comes with a dedicated lift, its own private lift lobby in the basement car park and four designated carpark lots.

The roof terrace of the penthouse has a private pool and a barbecue pit among other facilities.

On the lower two levels of the exquisitely furnished residence are supersized living and dining areas, a "secret" den with an entrance concealed by a rotating cabinet (like in a James Bond movie) and five bedrooms, BT understands.

A freehold project, The Marq comprises two 24-storey towers with 66 units. It received its Temporary Occupation Permit (TOP) in 2011.

In terms of actual penthouse transactions, the highest absolute price quantum achieved to date was the S$51 million that Alibaba co-founder Sun Tongyu paid for the sole penthouse at Wing Tai's Le Nouvel Ardmore in 2015, based on caveats information.

The price reflects S$3,757 per square foot based on the 13,573 sq ft strata area spanning the top two levels of the 33-storey freehold project. The unit has five bedrooms, with a family area and a study area on Level 32. A private pool, private foyers, roof terrace, a gym and an entertainment area are on Level 33.

The 42-unit project, designed by Jean Nouvel, received its TOP in 2014.

In terms of psf of strata area, the most expensive non-landed residential unit to have been transacted was not a penthouse but a 3,003 sq ft four-bedroom apartment on the 20th storey of the Premier Tower of The Marq which went for S$6,840 psf in 2011. The absolute quantum worked out to S$20.542 million.

(The Marq on Paterson Hill, where developer SC Global is still keeping the 17,500 sq ft penthouse)

GuocoLand's Wallich Residence is expected to receive its TOP later this year. The finishings and fittings of the super penthouse, occupying Levels 62 to 64, have yet to be completed; the layout of the unit can be customised to suit the requirements of the buyer.

The top level of the super penthouse has a private pool, pool deck area, cabana, jacuzzi room, entertainment area and a cantilevered balcony with panoramic views including of the CBD, Marina Bay and Sentosa.

The super penthouse comes with a dedicated lift but there is no dedicated carpark lot; Wallich Residence is part of a mixed development known as Tanjong Pagar Centre built on a site with 99-year leasehold tenure starting February 2011. This leaves a balance tenure of about 92.5 years.

Wallich Residence occupies the top 26 levels of the development's 64-storey tower; below the apartments are the offices, known as Guoco Tower.

The mixed-use integrated development's second tower, which is 20 storeys, houses the 222-room Sofitel Singapore City Centre which will be opening soon.

Tanjong Pagar Centre also has a retail podium and an urban park.

Wallich Residence is part of the last phase of the project to be completed. The other components have received their TOP in stages starting last September.

To date, GuocoLand has sold 19 of the 181 units in Wallich Residence – all for above S$3,000 psf.

The sold units comprise a mix of one, two and three-bedders. Facilities for the residents are spread over Levels 1, 39, 52 and 62 – and these include pools, a gym, library, theatrette, sky gardens and an observation deck at a cantilevered balcony on Level 62.

Property consultants expect super penthouses like the ones at Wallich Residence and The Marq to appeal mostly to foreign ultra high net worth individuals.

As Edmund Tie & Co chief executive Ong Choon Fah said: "These are really bungalows in the sky. Well-heeled Singapore citizens have the option of buying landed properties in Good Class Bungalow Areas.

"For head honchos of big foreign companies, a penthouse in Singapore can double as a private office and a place where they can entertain their guests and business associates."

Singapore luxury home prices have fallen in the past few years – the reverse of what has happened in most regional markets – offering an attractive value proposition, she added.

Written by Kalpana Rashiwala for The Business Times