Vendor Managed Inventory (VMI) has been one of the most valuable strategies that provides a number of benefits for both suppliers and customers. There was an impact on the proposed improvement practices listed, including VMI that enhanced and smoothened spare parts supply chain management. For suppliers, it can help to improve customer satisfaction by ensuring that they always have the products they need in stock. It can also help to reduce inventory costs by eliminating the need for the supplier to carry excess inventory. For customers, VMI can help to free up resources that can be focused on other areas of the business, such as sales and marketing. It can also help to improve inventory visibility and accuracy, and reduce the risk of stockouts. In this study, the services provided at residential complexes of the case study in Riyadh, Saudi Arabia have been listed, and then have found the most critical services to the tenants by conducting a scoring questionnaire. These services have been analyzed and listed the most common issues and have went through their supply chain process to rate the supply chain interruption risk. The highest rated risk service has been picked up as an example to apply the forecasting methodology. The historical data has been used for the elevators main board to draw the curve of occurrences probability. The curve equation has been found in order to use it as a forecasting tool. The finding shows the upcoming year expected demand using the mathematical calculations.