When sourcing used offset equipment, you must prioritize the mechanical condition and automation level. Key specs include the maximum printing speed (e.g., 15,000 sph), the number of color units (2, 4, 5, or 6-color), and the maximum sheet size (e.g., 720 x 1020 mm). Crucially, check the total impression count; machines with lower impressions generally have less wear on the cylinders. Ensure the machine features automatic plate loading (APC) and remote ink control systems to reduce setup times and labor costs.