Nitemare

An alternative would be to get yourself over to the Rowes Wharf Water Taxi station in Boston. Buy a ticket for a later water taxi ride to Logan Airport, the ticket price includes luggage storage. Leave your bags with them and explore Boston to your heart's content. They are right near Faneuil Hall and the Freedom Trail, etc. Or, most hotels will hold your bags for a nice tip. $20 for 4 bags should do it.

@princeton123211 is right, the flat rate taxi works out to about $100 to anywhere in Manhattan with tolls, fees, and tip. Uber can be a little less or could be quite a bit more. Nice thing about cabs is you follow the signs to the curb where they pick you up, while ubers require more walking to find their location There are no "day passes" for the subway. Pay per ride or you can get a weekly pass that works out when you take 13 or so rides in a week

If there are two of you, then their bus makes sense. For more than 2 a taxi would be a better deal. Flybus is also a good option, probably better than the NCL transport as it would take about as long but would be much less expensive

The "take our shuttle" suggestion is BS and is just a cash grab. Like their bus will be faster than a cab or have an alternative route???? Shameful

You might want to ask about toilets on TripAdvisor's Iceland forum. I haven't been in nearly 5 years -- back then, all the gas station toilets were free, as were many others. It was mostly in remote areas that you had to pay. But you will get current and more specific info there from folks who have visited more recently

I agree with @ljandgb. Any of the larger companies, like Troll, will be familiar with disembarking cruise passengers and would likely have a baggage storage solution for you

If there is a basket they would take USD. If it is a slot, then local only

Let's see, we walked from the east end of Canal street by the river, along the bottom of the island, up to midtown (45th street?) along the Hudson, across to midtown (as far as 5th avenue). Probably walked every street and avenue from 5th to 9th and from 50th to 36th. Also walked Broadway from Tribeca to Midtown and 5th and 7th avenues from midtown to Tribeca. So I can say those areas were clean and felt safe for us two staying on an AARP rate. It was tough to get restaurant reservations and theater tickets were harder to get than our other post covid visits, so I guess one could say that was a negative?

It's about an hour by taxi from anywhere in the city to the airport. It is important at KEF to arrive 3 hours prior to an international flight

yes, but the OP here isn't coming that weekend. We actually arrived in the Boston suburbs (Metrowest) on Marathon Monday (bad planning on our part) and our hotel was very fairly priced. Truly expected it to be worse and full of runners.

Easy to get to the subway, too, from there. To the airport or into the city for touring.

Drove by there this past weekend, as we journeyed from a Deer Island walk to the Market Basket Mothership. The Mrs. was surprised to see all the hotels there, more surprised when I told her it's where folks visiting Boston on a budget stay. "But it's so far away and not pretty and hard to get to town from here" she said. I nodded in agreement. October is expensive due to Leaf peeping and college Homecomings and conventions.

You really SHOULD see the city, it's vibrant and alive and pretty darn special. We were there 2 weekends ago for 4 days and it was amazing. Clean, fewer homeless than we expected, the subways were running on time and are cheap, and we walked and walked all over the place. Ignore what you see on curated TV and websites and ask people who have been there

Some Quincy hotels have dedicated shuttles for their guests to the airport and cruiseport. Ask them before you pay for an alternative

The Omni Parker House is right on the Freedom Trail and is one of the most historic hotels in the country. The Hyatt, assuming it's the one downtown, is fine, but nothing special and the neighborhood is awfully quiet at night