an example is i have 4th night free booked at eden roc cap cana..
The normal rate is $750 a night (plus taxes) the best available rate is 20% off that.
on the FHR site, you can book at the BAR rate ($595) or you can book at the base rate with the 4th night free which shows up as $562 which is 25% off.
so while 4th night free sounds great, in this case i'm only saving 5%

i don't think i've ever seen fhr rates on the website include taxes and fees..