(Day is approximate.)
Though the main hotel buildings have been demolished, this building remains. I've seen it suggested this was the garage for the hotel limousines, but it looks large enough that it probably served other purposes too. Can anyone shed more light on its history?
Currently it is used as a showroom for Maybach (high-end Mercedes) cars.
I've guessed the completion date as 1920, the same as the main hotel building. [Update: the building was completed in 1921, see comment below.]
Completed in 1921
The PWD report for 1921 says:
40. Principal Works of a Private Nature.—The additional residential wing and the large two-storeyed garage at the Repulse Ray Hotel on R.B.L. 142 referred to in last year's Report were completed, and a large block of servants’ quarters was erected.
I've updated the completion date.
Completed June 1921
The new West Wing Extension and the Garage of the Repulse Bay Hotel was to be completed in June 1921 from a report in the Hong Kong Telegraph in late May 1921
Source: The Hong Kong Telegraph, page 4, 20th May 1921