Understanding customer preferences for energy-saving building technologies is crucial for policymakers in the context of behavior, energy, and climate change to design effective incentives such as the Inflation Reduction Act (IRA) household rebates. Traditional models of customer preferences have been based on a rational lens that assumes customers make decisions based on maximizing their utility or satisfaction. However, scarcity, the perception of limited availability, can also shape customer preferences and disproportionately affect low- and moderate-income households. This research compares customer preferences for IRA rebates using a scarcity lens versus a purely rational lens. We simulate 10 building technologies across 550,000 households, comparing rational and scarcity-based factors by varying a customer preferences of immediate building technology costs, simple payback, and total utility bill savings. Our findings reveal significant differences in IRA-eligible building technology preferences, which can inform policymakers in deploying and adjusting building decarbonizing programs Our results have important implications for federal, state, and community policymakers interested in understanding and addressing customer preferences and deploying effective and equitably decarbonizing programs.