The apartment, designed by Brown Falconer, is the amalgamation of two apartments on sub-penthouse level 34 in 'The Adelaidean' building on Frome Street.
Colliers International's Nick Pelvay says the record sale is an indication that people are increasingly looking to invest and live in the Adelaide CBD.
"The Adelaidean was only released to the market in May and we've received overwhelming feedback from buyers so far, with many apartments under negotiation," says Pelvay.
"This is an excellent example of a development that is able to meet buyers' changing needs and lifestyle interests."
Colliers International's James Polacek says the Adelaide apartment market is booming with more people looking to downsize and live closer to the CBD.
"There has been a significant interest from buyers looking for three or more bedrooms, with an increasing number of purchases of more than $1 million," says Polacek.
The City of Adelaide council is trying to push for more people to come and live in the city's apartments by rewarding owner-occupiers who purchase off-the-plan apartments in the next two years with a five-year hiatus from paying rates.
The City of Adelaide aims to increase the Adelaide CBD population to 28,000 people by 2020.
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