Hotwire Hotel: Timing for 5 stars

[Dunner]

Hi I am a newbie to the site and would like to know what timing is better for booking my 5 star room to get the best rate from April 17th to the 21st? I would prefer to stay in Belligio, Venetian, or Wynn. I would like to try the auction route but need to take a chance I guess on which hotel or is thier a better way of finding out this?

Thanks... Dunner