Following the commodification reform of residential properties in China, multi-unit residential buildings (MURBs) have emerged as the most prevalent housing type owing to their high economic value and convenient infrastructure. In recent years, there has been an increasing concern regarding the potential negative impacts of MURBs on residents. To address this issue, in this study, a survey was conducted among 552 purchasers, and methods such as expert questionnaires, factor analysis, Kano two-dimensional quality, and analytic hierarchy process (AHP) were employed to evaluate the significance of 19 factors related to the quality of MURBs’ unit spatial layouts. An index model summarizing their utility was developed. The research findings indicated that spatial function held the greatest influence, followed by indoor environment, with spatial organization ranking last. Moreover, we analyzed the influence of preferences on satisfaction and the variations in preferences based on sociodemographic factors. The results aim to assist real estate developers and purchasers in evaluating the quality of housing spatial layouts, ultimately enhancing the overall quality and comfort of MURBs.