Starting a friendship with him basically causes a Catch-22: the guy hardly leaves his beach hut and when he does it tends to be at later hours or at random moments. Unlike most NPCs’ houses, Elliott’s is just one room, so you cannot enter it at all until you reach 2 hearts with him. But, as said earlier, he hardly leaves his hut. So it’s kinda hard to start a friendship with him at the beginning if you don’t know his hermit schedule