We did a 7 day on NCL out of MIA. Our bill was a little higher than usual @$450. That included $210 from the casino ($5 for slots, $65 for shopping, etc & took home $140). We splurged & ate at 3 cheaper speciality restaurants @20% off. Also bought a $250 future cruise credit (really $150 out of pocket).

NCL doesn't charge a 3% fee that some other cruise lines charge for pulling out cash at the casino using the shipboard account. We only took out a little from the casino for our needs. One could pull out $$ as one could use a points based CC to pay the final bill. We didn't want to abuse the privilege & deal with carrying alot of cash around MIA.

We saved alot by bringing a 3L box of wine in our luggage. They are usually looking for liquor bottles. We also saved alot by doing our own exercusions. One example was the cruise line wanted $45-50pp and we got a similar exercusion for $20pp that was better. :)

So how did it go? One other thing you MIGHT want to take into consideration is ship size. Sure the Gimoungous ships have tons to do, but they typically also have tons of people wanting to do them and then when you get to port it take s along time to get on and off the ship. $0.02

From a NCL gold member on many of her cruises, one thing that I would add to the final charges is (not counting the casino losses / or, winnings ;) )
for all those bingo games that people play, usually on sea days in the lounge and even those "instant" game pieces before the shows in the main theater -

We've seen couples screamed with the final bills in hand, lined up at the reception desk, trying to understand why it was so much (not unusual to be as much as $400 or $500, or higher after 3 days of morning & afternoon game sessions, with multiple games played on those digital scorecard boards at $40 or more per session x 2 people) It's easy to just sign & approve the charges as all they need is your room key card to post it to the Onboard Account.

Last minute or gift items ("on sale") purchased in the gift shops or the mega ship's "shopping mall" can also add up quickly, especially if you forgotten a swimsuit, need a pair of shorts or other things. Plus, there will be those daily special sales ("designer" watches & jewelry, duty-free items) and last but not least - professionally photos/packages as taken onboard. And, that's with a full bypast of the art gallery & its auction with promises of free shipping & no taxes)

Some cruisers are known to stop at the desk midway thru the trip to check on their running balance on the account, to avoid surprises and to put a curb on more charges being "signed" off for being posted to the cabin.

Great advice