This article, using a descriptive-analytical research method, examines the obstacles to the realization of renting vacant houses based on the Completion and Rental of Residential Units Law enacted in 1977. In the final years of the Pahlavi regime, the housing crisis became one of the main social and economic challenges, profoundly impacting people's lives and the structure of society. The rise in tenancy and the shortage of suitable housing placed significant pressure on tenants, making the need for a comprehensive and effective solution essential. In this context, the Completion and Rental of Residential Units Law was designed to regulate the rental market and utilize the potential of vacant houses to provide housing. The primary goal of this law was to create balance in the rental market and facilitate people's access to suitable housing. However, the implementation of this law faced numerous challenges and obstacles that hindered the achievement of its objectives.

The findings of this research indicate that the accurate identification of vacant houses, due to the lack of integrated and precise information systems, was one of the main challenges. Additionally, resistance from property owners to renting out vacant units and social concerns regarding legal changes were among the other significant obstacles to the implementation of this law. Many property owners, fearing a reduction in income or issues arising from renting out their properties, were reluctant to participate in this initiative.