All the authorities find essential is the cooperation with the designer and not the brochure that the latter floats. Check the terms of payment for phase / s of building. It will be very unlikely to get some redress from any regulatory body whether you have withheld payment or not met the negotiated conditions according to the deal. If you are ready to accept the penalties granted to you for your defaults, the Consumer Grievances Forum may require specific performance on the part of the Builder.