The unit price contract prepared by the client indicates contract items and estimated quantities deemed necessary to accomplish the proposal objective. Moreover, the bidder is required to allocate unit prices for these unit bids. This paper presents a model concerning the formulation of tendering unit bids for unit price contract. The proposed model attempts to objectively exploit variation trends in client-provided quantities for the allocation of rates to unit bids in attempt to achieve the maximum benefit for bidder. Often the unbalance in distributing the items markup of the tender would result unreasonable unit prices. The proposed model has been devised to determine the unit bids of the unit price proposals in order to give reasonable unit prices and also maximize the expected profit. The model is especially useful for mega and complicated projects of many items. Finally, the developed model has the remarkable feature that, for given project information, no other means of unbalancing will yield a greater expected profit under the given constraints.