This report is the fourth in a series that unpacks the barriers to access that families face, the variety of solutions that navigation organizations have developed, and the challenges that limit the reach and impact of those solutions. This series offers recommendations for how to help navigators address these challenges and support more families and students. This report discusses the issue of scaling and sustaining navigation supports. There are no easy answers to the challenge of sustaining and scaling navigation services. Reliable revenue streams are hard to come by, and navigation organizations must carefully consider various funding models while prioritizing the best interests of the families they serve. The strength of family-navigator relationships makes navigation inherently unique for every family but also resource intensive -- requiring navigation organizations to think creatively and strategically to lower costs and improve efficiency. By diversifying revenue sources and leveraging strategies like tiered support levels, peer support, virtual interactions, and AI-powered research, navigation organizations can do more to sustainably increase their reach while continuing to deliver high-quality services.