Jeju Island Living: Tips for a One-Year Stay
I tried living in Jeju from November 2020 to November 2021. At first, I worked for a company that allowed remote work, so I spent almost all my time on the island. Then I changed jobs in August and lent my room to some friends, so technically, it wasn't a full one-year stay. Still, while I wouldn't call this professional advice, I feel like I can share some of my impressions, so I decided to organize my thoughts into a few topics.
A Car is Essential in Jeju
If you've traveled to Jeju, you probably already know this, but it's a very difficult place to live without a car. If you plan to just stay in the neighborhood where you rented your room for days on end, you might be fine without one. But you have to go to the grocery store and occasionally visit tourist spots, so a car is an absolute must.
Some people try to rent a car in Jeju, but personally, I recommend bringing your own from Seoul. Of course, if you are extremely protective of your car, I wouldn't recommend bringing it because of the salty sea breeze, but I doubt someone like that would do a one-year stay anyway. Just keep in mind that if you do bring your car, you'll need to run it through the automatic car wash frequently. Whether it's a car or electronics, things wear out quickly once they come to Jeju.
If you decide to bring your car, pack it as full as possible with clothes and luggage, and send it via a vehicle transport service. You can take a separate flight and pick up your car as soon as you land. The transport companies manage their schedules carefully so customers can start traveling or moving right away, so don't worry too much and just trust the service. As of 2023, the cost is about 300,000 KRW one way.

Park at Halla Gymnasium
There are times when you need to make a quick trip back to Seoul from Jeju. Taking your car to the airport and paying for parking is so expensive that it's hard to even consider. In these cases, I park at the Halla Gymnasium parking lot in Jeju City and take a taxi or bus to Jeju International Airport. Of course, since it's free, there are almost never any spots, so you have to go at dawn or arrive early to park. Still, it's a large lot, so if you wait around, a spot will eventually open up.
If you go to the gymnasium, you'll notice that it's a bit confusing to tell what is a parking space and what is just the road. The thing to be careful about here is that there's a fire station nearby. If you accidentally park in the fire zone, you could get a ticket and have your car towed.
Get Your Services in Seoul
Working for a long time in Jeju without a proper desk and chair took a toll on my body, so I started working out. I got personal training, and the price was the same as in Seoul. However, I felt their ability to teach the exercises was at a junior level compared to Seoul standards. I especially couldn't trust them when it came to injuries. Whenever I asked a question, they would look it up on the internet before answering, which made me quite suspicious.
If you eat at a highly-rated restaurant (usually places selling pasta), the food doesn't seem any better than what you'd find in Seorae Village or Yeonnam-dong (trendy Seoul neighborhoods), yet the prices are about 5,000 KRW more expensive. I wonder if it's because of the nice views, but then I think, could the land prices here really be higher than in Seoul, which is notoriously expensive on a global scale? Aside from sashimi and dishes made with local Jeju seafood, the food in Jeju is generally more underwhelming than expected.
When it comes to services provided by people, Seoul is overwhelmingly better. The cost-effectiveness goes without saying, and the quality is lower than in Seoul, so I recommend keeping the various programs or classes you take in Jeju to an absolute minimum during your one-year stay.

Skip Jeju City and Seogwipo City for Housing
If you came to Jeju for a one-month or one-year stay, you probably came to work remotely or take a long vacation to enjoy some downtime. But if you rent a place in Jeju City or Seogwipo City (the main urban centers), it's hard to find that relaxation. It's like going on a trip to Southeast Asia and only hopping between shopping malls.
The prices are a bit cheaper in Jeju City and Seogwipo City. The rooms are a bit smaller, and the only view you'll get is of Hallasan (Halla Mountain). If you come to Jeju, you should have the ocean in front of you and Hallasan behind you. Or, you should go deep into the mountains and feel a sense of solitude that goes beyond just being quiet.
If you came alone, try looking for a studio or a 1.5-room apartment. If you can find one for under 500,000 KRW a month, you've found a good deal. If you came with your family, I recommend renting an entire house. Since you have kids, a place where they can run outside and play happily at any time is best. I especially recommend somewhere near the beach. To borrow the words of a friend's daughter, she absolutely loved being able to swim and play in the ocean every day.
The 'Yeonse' (yearly rent) system, which is unique to Jeju, is something that only applies to people doing a one-year stay. With Yeonse, it's common to pay for 11 months and get one month thrown in as a bonus to complete the year, so if you want to save money, sign a Yeonse contract. The downside is that you won't be able to experience living in different parts of Jeju. You need to think carefully about what kind of lifestyle you want in Jeju before deciding so you won't have any regrets.

Jeju's Winter is No Joke
Since Jeju is in the south, many people think the winters will be warm and easy. That's half right and half wrong. It is warmer, so it's nicer to live in than Seoul. However, the fact that you can't go outside because the wind blows so hard is exactly the same. If you really want to feel nature slapping you in the face, try going outside in the winter. No matter how much you keep your guard up with clothes and hats, it will batter you until you're in tears, giving you the full experience.
Another reason Jeju's winter is no joke is the snow. Coastal areas don't get much snow, and even if they do, it melts quickly, but if you go to the mid-mountain (Jungsangan) areas, you will literally be buried. Whether it's rain or snow, if you encounter it in the mid-mountain areas, you won't be able to see in front of you no matter how fast you run your wipers. Especially if you booked your accommodation in Seogwipo, you will inevitably have to cross over Hallasan to get to Jeju International Airport, and it is incredibly dangerous at this time. For this reason, even if you ignore everything else, I highly recommend changing your tires before driving down to Jeju.

Jeju is more fun than you'd think, but also more boring than you'd think. In my experience, trying to live too perfectly makes it exhausting. It's a place where you can be fully satisfied if you acknowledge what it lacks and let go of your expectations a little.