In 2016, only one in five eligible U.S. households received rental assistance and waiting lists averaged two years nationally. The gap between available rental assistance and need requires systems to allocate this scarce resource. The way potential rental assistance recipients experience and navigate these systems is likely to shape who ultimately receives assistance. We draw on repeated qualitative interviews (N=238) with low-income New Haven residents (N=54) to examine how participants understand and navigate rental assistance applications and waiting lists. Participants encountered multiple challenges in their search for rental assistance. They described an opaque and complex application and waiting process requiring significant knowledge to navigate. They also described considerable labor associated with monitoring waiting lists, a challenge made more difficult for some by their lack of a stable address. Additionally, participants described significant labor and knowledge required to strategically navigate prioritization systems that often required them to advocate for their deservingness of scarce housing resources. Our findings suggest that the allocation of rental assistance through complex processes that depend on applicant knowledge, labor, and advocacy may create barriers to housing, particularly for more vulnerable and marginalized housing seekers.