We've rented homes for the past four years, and we've always booked around a year in advance. Last year we booked 8 months in advance, and that was the latest we've waited. A lot of the really nice homes book up pretty fast, so if you know your travell dates and your plans then I say go ahead and book! I haven't heard of owners giving deals for booking far in advance, though. We've only seen owners giving last-minute rental deals.