It looks like in these prices you are charged anywhere from HK$250-$300 RT for the ferry, which doesn't seem like much of a deal, given that ferry tickets usually cost HK$125-$175 each way, depending on when you go. You would be better off buying the ticket and sauna separately, giving you more flexibility (there are two ferry companies, you might want to stay overnight, might want to go to another sauna, etc).

Typically when I have bought the package, I just go to the ferry terminal, and walk around until I find the best deal for the sauna I want to visit. I was under the impression that I ended up with a free ferry trip by buying the package, but that could have just been marketing and they bundled the cost into the price of the services instead. Learn something new every day...

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