Sociological research on school choice has mostly been dominated by studies analyzing the experiences of middle-class families rather than marginalized or minority populations. Drawing on 8 months of ethnographic case study research, this article explores the school choice experiences of disadvantaged families accessing publicly subsidized low-fee private schools (S-LFPSs) in Buenos Aires. We built a bounded-rationality framework to understand how disadvantaged families deal with structural constraints and negotiate their preferences to produce different, but predominantly reflexive rationalities of school preferences. In detailing our findings, we intend to provide "a realistic look at the cognitive and social processes of choice making" while addressing the equity implications of these dynamics--that is, whether S-LFPSs increase educational opportunities for students in economically disadvantaged areas or not--and problematizing the gaps, ambiguities, and enforcement shortcomings of the public subsidy for private schools' policy.