G.O. Service is a union sub-contractor focused on general conditions work, such as interim cleaning, debris removal, safety rails, and temporary partitions. G.O. Services also operates buck-hoists and elevators. Welcome to Chicagoland AGC!G.O. Service is a union sub-contractor focused on general conditions work, such as interim cleaning, debris removal, safety rails, and temporary partitions. G.O. Services also operates buck-hoists and elevators. Welcome to Chicagoland AGC!