While I was in Jeju, I stayed at an incredibly wonderful place called Yeha Guest House. Just a few blocks from the bus terminal in Jeju City, you can access the whole island easily, and they rent bikes out at 5,000￦ a day if cycling's more your thing.
The staff is multi-lingual, offering services in Korean, English, and Chinese, and they are more than helpful with both big and little things. They keep a book of menus and a collection of those restaurants' coupons on hand so you can get food delivered to the place, and they volunteer to call the order in for you.
I hadn't booked my passage home until after I'd climbed Hallasan, and the kind woman on staff actually called and made my ferry reservation for me. It saved me loads of trouble, as I can't speak Korean, and her timely call got me the last slot on the ship.
They have a kitchen you can use at any time and they give you eggs, bread, cheese, and jam for free so you can cook things for your breakfast. Trying to make eggs here gave me the confidence to make good omelets here at home.
They give you everything you need. All you have to do are dishes.
They have an awesome common area where you can hang and chat with other guests. I got to practice my old German skills on boarders there from Deutschland, and I met my hiking partner there, as well as many other fascinating people.
There are books you can read, movies you can watch, and a guitar you can pick up and play...
...not to mention copious amounts of games to try!
They have computers and Wi-Fi there for free, and you can even make free long-distance calls to a fair amount of countries.
There's a wall with money from around the world and a ranking system so you can see what other travelers did and what they liked the most.
I had a cell phone and wasn't interested in tours, but they can set you up with cell phone rentals and give you discounts on affiliated tours.
They also sell all kinds of handy/useful things like postcards, postage, raincoats, etc. You can check out sunhats and umbrellas, and there's a little thrift shop where you can buy old travelers' excess things (shampoo, etc.) to use. All proceeds go to charity and when you leave you can donate back to the little front desk shop.
They have maps all over to help you plan your days and can give you lots of information about how to get around.
They also gave out complimentary Jeju chocolates and Jeju oranges (things Jeju is known for). Some of these things are available at the guest house for lower prices than you might find other places.
I stayed in a dorm-style room with bunks and other female boarders but it was incredibly pleasant. At $25 a night during peak season it really wasn't bad at all, and booking through their site - also multilingual - was actually a breeze.
If you ever visit Jeju Island, I definitely recommend them. Check them out for yourself if you'd like:
www.yehaguesthouse.com
