Islamabad Development Authority (CDA) has hired the services of a consultant firm for designing and supervising the construction of Zero Point Flyover, a source in the authority said. He said the project would be completed within one year at an estimated cost of Rs400 million. The firm - AAA - which filed the lowest bid would first prepare a design of the flyover and then supervise the construction work. The contract of the project would be awarded later, the source said.