Installing a PV system requires the exact anchor for any roof. Sometimes unfortunately, ancient roofs require global configuration and customization of the anchoring system. This is an orderly room of a former Roman watchtower. The roof beams do not match the tiles, and modification of the brackets was the best solution to secure the photovoltaic modules on the roof. Even the solution of micro inverter was an obvious choice because of the shadows and the possible arrangement of photovoltaic modules.