Ridiculous airfare??
 

I've been constantly checking the fare daily for the flight from LAS to SJU on Dec 20th til Dec 29th. The fare is $800 and above. I've tried all the airlines that offer flight to SJU from Vegas. Nothing goes below $600. When is a good time to book it? :confused: Should I clear the cookies and try again? will the fare be different at all?

That's peak season to beach locations. You may not find much better.

It is more likely that fares go up than down. Shaping up to be a good economy so people are willing to spend. You have to ask yourself whether you should grab what you can afford now or face the prospect if a $1,000+ ticket down the road.