"Ahu" are stone platforms on which many moai sit. There are 313 known ahu and 125 of these carry moai. The biggest, Ahu Tongariki is 220 m (720 ft), and had the most (15) and tallest moai.
Many talk about a guest worker program. I think most reasonable people believe that a guest worker program in the farming industry, perhaps in the gardening and landscape industries, is reasonable.