It may be three years before Double Bay Residences is completed, but some buyers of the sold-out, 646-unit condominium at Simei Street 4 have already cashed out for a profit. The 99-year leasehold project was launched in March last year amid much uncertainty in the property market. Units went for as low as $409 psf, with the average selling price in the $600 to $650 psf range. With the property market...