Rural homestay tourism plays a pivotal role in fostering inclusive economic growth and cultural preservation across underserved communities. However, long-term sustainability remains fragile due to weak financial practices and inconsistent service quality. This paper proposes a sustainable Finance-oriented Service Management (FOSM) framework that integrates financial management with service delivery strategies to enhance the performance sustainability of rural homestays. Drawing on the Quintuple Helix Model and aligned with Sustainable Development Goal 8, the framework identifies how financial literacy, income diversification, and service excellence jointly influence the socio-economic well-being of homestay operators. Through a conceptual analysis of current challenges, the study highlights the moderating role of financial practices in translating improved service into tangible economic outcomes. This paper contributes a unified model to guide policy, capacity-building, and innovation in rural tourism ecosystems, with direct implications for empowering micro-entrepreneurs and strengthening rural resilience.