I had paid for a Haleakala sunrise tour via Polynesian Adventure
through HawaiiDiscount.com, and the driver from PA failed to turn up the
morning of the tour. I called PA directly (since they were the ones I
had to confirm the tour with) and PA offered me a free tour the
following day and said I would be refunded any cost of the tour I had
missed out on.

Lots of talking to PA, in which I found out that they could not
refund me directly because I had booked through a 3rd party. Which was
fine, until I e-mailed HawaiiDiscount.com to ask them about their refund
policy and to detail what happened. They not only got my credit card
info wrong, but flat out kept insisting me that I never received a
comped tour, and then changed their claim that I went on the tour I had
paid for, so I didn't deserve a refund.

Called both the phone numbers
listed on their website once a day for three days trying to get someone
on the phone. When I did finally talk to someone named John, he made it
clear he wasn't listening to a word I said because I could hear his cell
phone (speakerphone turned ON) the entire time. He "promised" to call
me back, didn't, and my subsequent phone calls and voicemails were never
returned.

Had to go through a huge ordeal with my credit card company, but it
was a good thing that I had exact times and dates of events, names of
people I spoke with at PA, and just generally a very detailed account of
what happened, while the only reason HawaiiDiscount.com could tell my
credit card company was "Customer went on the tour." Both Polynesian
Adventure and my credit card company were great though, and both PA and
credit card company told me right off the bat that I didn't go for the
tour that I paid for on the day I paid for it, so I should get my
refund.

Lesson learned: Book directly with whatever hotel or tour company you
decide to go with. It's worth the extra $10 or whatever dollars if
something comes up. Have also had bad experiences with big 3rd party
sites like where the rates ended up being cheaper if I had
booked directly with the hotel, so best to call the hotel directly/check
on the hotel website and find out any specials going on.