Ector is the most amazing of hosts and was nothing but helpful with us throughout our stay. Answers quickly and is flexible when guests have late arrival (due to delayed ferries). In addition, he supplied us with plenty of tips on what to do, beer/wine to enjoy while watching the sunset from the veranda, and he also drove us to/from Ermoupolis and had a few drinks with us.
Syros is an amazing island, and the location of Ector's AirBnb is excellent: five minutes walk down to Kini which has a gorgeous beach, with a number of restaurants, tavernas and bars. Perhaps a bit quiet in the evening, but bus (1,80€) or taxi (~12€) can easily bring you to Ermoupolis. Very authentic village and island, and luckily no sight of flocks of tourists. Absolutely recommended!