Firebird Electric, U.S should pursue the "buy" decision for the housing parts. the following reasons are: The comparison between the costs associated on the"make- or buy" decision showed that the firm can save a lot if they were going to continue pursue the latter. rong inter departmental coordination in the whole organization. Departments included in the product development process such as product design, purchasing, quality assurance, sales, production control and materials management are highly integrated from each other.