There are many locations to stay at in Ios but I'd definitely recommend Far Out Hotel & Spa. The rates were pretty reasonable - under 100 euros per room. The rooms we all had were spacious and comfortable with sea views. The pool and pool bar area are fantastic as well. Bring a tiny bit of patience when you check out at the front desk, it was the only down side of the whole process. I wouldn't let it stop you from staying here though. We loved everything else about the location and its a quick walk into town. You can also rent ATV's and park them out front of the hotel which I highly recommend!