This chapter examines daily wage data from the building sector, identifying patterns and bias that challenge their use as proxies for pre-industrial living standards. Through an analysis of over 30,000 wage observations from Naples (1800–1860), the study moves beyond the traditional “skilled-unskilled” dichotomy by adopting a “wage spectrum” framework that captures variations influenced by sources, occupations, time, and space. The findings demonstrate significant wage differentials based on archival sources (ecclesiastical, private, and public), highlighting potential selection biases in historical reconstructions. Occupational analysis reveals wage variations not only between but also within skilled and unskilled categories, reflecting job-specific demands and worker characteristics. The study identifies substantial seasonal wage fluctuations tied to agricultural labor cycles and documents a persistent “urban premium,” with Naples maintaining consistently higher wages than peripheral rural areas within the Kingdom. This intra-state wage disparity, often overlooked in building wage analyses, provides new insights into regional economic inequalities in pre-industrial societies.