Apartments at Casa Merah changed hands at above $800 psf in the secondary market between Sept 11 and 18. The surge in price was probably because of the successful launch of neighbouring Optima @ Tanah Merah in August. The new development, which will sit next to Casa Merah along Tanah Merah Kechil Avenue, saw apartments sold at above the $800 psf level. As at end-August, all the units at The Optima were...