Development and Application of an Investment Decision Support System Based on Life Cycle Cost Analysis: A Case Study on Residential Complexes

The growing intricacy and financial risk of residential complex projects in emerging nations require dependable decision-support tools for early investment evaluation. This research presents the design and implementation of the Residential Investment Decision Support System (RIDSS), a specialized platform based on Life Cycle Cost Analysis (LCCA). RIDSS facilitates stakeholders to assess financial feasibility by employing economic indicators such as Return on Investment (ROI) and Profitability Index (PI), while also integrating sensitivity analysis (±10% or ±20% change in cost) and dynamic cost adjustment mechanisms. Through the application of a real case study in Iraq, the system demonstrated its capability to simulate both financial success and failure, thereby enabling users to explore various investment conditions. Projects with an ROI below 15% or PI values below 1.0 were flagged as non-viable projects; in such cases, users were able to perform sensitivity testing and cost adjustments efficiently (±10% or ±20% change in cost and revenue). The results confirm RIDSS as a practical and interactive tool for early-stage decision-making in residential development, with promising potential for future expansion into multi-criteria frameworks and real-time data inputs.