This work concerns software product lines (SPL); it comes from the experience gained collaborating with Berger-Levrault, a French society leader in Human Resources systems. This enterprise serves many French and European territorial communities. They had a variability problem associated to the differences of applicable legal rights in different countries or territories, and this activity was performed manually at a high cost. On the other hand, functionalities were common and mandatory and did not very much. The crucial issue in SPL development and practice is to manage the correct selection of variants. However, no standard methods have been developed yet, and industry builds SPL using on-the-market or in-house techniques and methods, aware of the benefits a product line can provide; nevertheless, this development must return the investment, and this is not always the case. In this work an approach to variability management in case of legal rights applicability to different entities is proposed. This architecture-centric and quality-based approach uses a reference architecture that has been built with a bottom-up strategy. Variability is incorporated to the reference architecture at abstract level considering non-functional properties. A "production plan" to reduce the gap between abstraction and implementation levels is defined.