In recent years, significant economic and human loses have been caused by earthquake events across the globe, particularly in developing countries, where non-seismically designed buildings constitute a significant share of the existing stock. Algeria is one of those cases and has witnessed earthquakes in the northern part of the country, which indicated the urgency to establish a robust disaster risk reduction strategy. Building exposure is one of the main model components for natural hazard risk assessment and, typically, exposure models are defined from proxies, such as national census databases or local expert opinion, for the distribution of buildings and population. However, no specific indications on the best nature or size of a regional exposure model are available to provide guidance on large-scale seismic assessment studies. In this paper, a step forward is provided by engaging different Algerian stakeholders in the collection of in-situ building data through a user-friendly smartphone/tablet application, with the aim of aiding the development of building exposure and vulnerability models, as well as increasing the risk awareness among local population and practitioners. Subsequently, earthquake damage estimates are produced and evaluated over the buildings’ lifetime in terms of exceeding slight, moderate, extensive and collapse damage states. The computed damage metrics are also used to provide input on the importance and usefulness of the in-situ collected data as a supporting data source in the development of exposure and vulnerability models. A discussion on the possible sources and size of the exposure model and preliminary guidance on conducting in-situ surveys are provided, with a view to a possible re-use in other contexts (provinces) with similar building stocks to the region addressed in this study.