Grover,
there is some good advice here, especially from snapper, I would certainly book early, so you can then sit back with peace of mind knowing it is booked.

As for the luxury and executive phases, I have seen these used in tour operator adverts, but as far as I know no tour operator owns any villas, they rent from Management companies who are the people over there who look after the villas for private owners.

Why not cut out the middle man? book direct and get the full value, there are 3 links at the top of these pages for homes that are all privately owned and varified by the site owners to ensure this fact.