I've been on 50 cruises. Here are 5 things I never buy on the ships.

Most of the major cruise lines, like Carnival and Royal Caribbean, offer drink packages. But they can tack on hundreds of dollars to an already pretty expensive vacation.

Plus, the packages really vary across companies — some cruise lines give you 15 drinks a day while others have unlimited options.

Unfortunately, on every cruise I've been on, everyone (of legal drinking age) in the same stateroom has to make the same decision on drink packages. Even if you're traveling with someone who doesn't drink, they'd have to pay if you want a package.

Instead, I always order drinks à la carte when I want one. It saves me money and makes me really think about the drink I'm ordering.

One of my favorite parts of cruising is the excuse to get a pedicure beforehand.

Salon services, including pedicures, manicures, and blowouts, are available on a cruise, but I always skip them.

The prices are often much higher than the most expensive services at home. It's also nice to walk onto the ship already looking and feeling great.

In my experience, room service used to be included on many cruise lines. Although the option is usually still there, it now typically costs extra.

Instead of paying the fees, I just head to one of the included dining options — like the buffet or main dining room — to get snacks or meals. If I really want to eat in my room because I need some downtime or want to watch a movie, I ask if there are any to-go options.

I also take food to quiet areas on the cruise ship, like adults-only pools, if I want a chill spot that's not my room.

It can be tricky to keep track of your room key, which usually doubles as a form of payment and ID to get on and off the ship.

Most cruise lines have an abundance of lanyards for sale as a remedy, but I don't think they're worth it.

Instead, I just put my key card inside my phone case. Since I always have my phone with me, I also always have my room key.

One of the biggest expenses on a cruise, besides the actual booking, is excursions. Cruise lines offer dozens at ports of call around the world, but they're often very expensive for a solo traveler — let alone a family.

Instead, I like to explore the ports on my own or with a third-party excursion company. These excursions are usually cheaper and offer similar experiences.

But always do your research and read reviews before booking with a third-party company. Also, be sure that the excursion ends and gets you back to the ship at least an hour before it's set to depart so you don't get left behind.