The normal price on the cottage isnt the $500 a night they state - you can get it for $400 from other booking sites. At $195 a night its 50% off and if your looking for something for the weekend might be worth a look.
Dates are between now and 2nd of May. The retreat is at 15 Middle Pocket Road, Billinudgel, Australia, 2483.
Seems to be an ok place from the reviews - but never stayed there myself.