Third-Party
Not the magical 12%/15% that sometimes happens, but better than a kick in the guts.
I know some people say they raise the price with cashback deals to match non-cashback prices anyway, but I've just cancelled and re-booked all the accommodation for a holiday I have coming up in Japan in November to get this cashback, and the base price stayed the same. So there don't seem to be any funny games at play for Japan at least I'd say.
Exclusions listed:
Cashback is ineligible on the following:
-Any changes made directly with the hotel/property will invalidate cashback.
-Car rentals, flights, non-accommodation bookings.
-Use of any Booking.com refer-a-friend links, codes or any non-Cashrewards incentives (offers, links, newsletters, secret prices), unless stated as eligible on this site.
-Travel that is not consumed.
-Cleaning fees for homes & apartments.
-GST and other taxes.
-Fraudulent transactions.
-Purchases using any type of discount which lowers price advertised on the Merchant site, including but not limited to employee discounts, student discounts and price-matching.
U r right. The price is $600 more expensive than as usual for 2 days onsen stays in Japan.