In a bidding process, bidders have to define and estimate potential bid solutions relevant to the customer’s requirements. Afterward, based on several criteria (e.g. cost, due date), they have to select the most interesting solution to be sent as an offer to the customer. However, the lack of complete and accurate information makes the estimation imprecise and uncertain. In this paper, an approach is proposed to support the definition and the estimation of the potential Engineering To Order (ETO) technical bid solutions and the selection of the most interesting ones. The definition and the estimation of the potential bid solutions is supported by a new knowledge-based configuration model whereas the selection of the most interesting solutions is supported by a new multi-criteria decision making approach that takes into account uncertainties and imprecisions.