There is only one accommodation on Okunoshima, and that is the Kyukamura resort chain. The resort has a chain of hotels in different parts of the country, each having its unique theme. And this one is of course, the rabbits.
To book accommodations on the island, I highly recommend doing it on the English website itself which is actually done via Rakuten. To be honest, they don't have many styles of rooms and the hotel itself is rather basic. So wherever you book, you won't get much variety. It really just comes down to the prices.
I highly suggest booking 3-6 months in advance if you are traveling during the warmer seasons like late spring and summer. Those times are usually quite popular, especially during the holiday when locals have more time to island hop in the Setouchi area. During my first stay, I was planning a trip end of April and I booked about 6 months in advance because I knew many school children will have holidays. When I checked again 2 months before my trips, all the rooms were already booked solid. So make sure you do some research on Japanese holidays and plan ahead!
The "resort" is nothing fancy and quite bare bones.
Rooms are your standard Japanese traditional style with tatami and a sitting area. Nothing fancy, none of that in-room private bath thing, but most rooms have toilets. All rooms look out to the island.
There are two public baths for each gender - a big and a small bath. I believe some of the bigger rooms have a shower and bath in the room, but mine above does not. You will have to shower and bathe in the public one.
I think it's great if you have yet to have a traditional Japanese room experience, and want to attempt sleeping on a futon and tatami for a night without breaking your bank.
Prices are between $90 to $120 per person, with boarding.
Breakfast and dinner are both included in the price, which is great since options for eating is pretty non-existent on the island. All meals for buffet style.
What's at the buffet will vary depending on season. The first time during my stay, it was pretty standard - pasta, rice, an assortment of Japanese dishes like fish and stew, steamed vegetables, some local seafood and some sashimi, and of course soft drink bar plus dessert.
This second time, they put a lot of emphasis on oyster, grilled seafood and steak. There was a station of just grilled fish and grilled shellfish, plus different assortments of oyster dishes (fried, steamed, etc). The food is obviously nothing that will blow your mind, but if you want to try a good variety of foods and get some veggies into your daily intake, I think the buffet is great.
Breakfast is along the same lines. There are some western options, but most will be very Japanese like your typical rice, fish, soup and other little side dishes.
What's Different in a Stay vs Day Trip?
The main difference is that you will get to see the rabbits out and about during the night time as well, in a more quiet setting. If the weather is warm enough, there will be SO MANY rabbits just lounging outside of the hotel in complete darkness. You will be able to see them from your room. You can also of course, feed them too when there are less people around on the island.
More one-on-one time with the rabbits is always good right?
The resort also has some walking tours they offer guests early in the morning to see the sunrise on a good day. They're just 30 minute quick tours, free for staying guests, just before breakfast time.
You really get to have a good feel of the island once a lot of the day tripper leave in the late afternoon and early morning. There so much history on the island, where with no one around, gives you this eerie feeling when you're walking through a trail or next to one of the abandoned buildings.
You can also see both the sun set and rise on the island, since it's relatively unobstructed by tall buildings and such. On a good clear day, you can even see some stars in the sky.
Other Tips on the Island
If you are staying on the island, make sure to pack a lot of rabbit feed with you. Go to the family mart I talked about in my previous post, and stock up. I would get at least one bag of pellets and two bags of lettuce and carrots for each person. If you aren't able to stock up, get what you can.
Always feed sparingly during the day, and save your feed for the night and early mornings. In warm weather, there will be a lot of rabbits out by the hotel during that time, and they will all get pretty greedy then.
Of course if you need human snacks too, stock up at family mart too!
If this is your very first time on the island, and you want to see the island, plan ahead with the train and boat schedules so you can do everything and still be able to chill in the hotel room, bathe, feed rabbits multiple times and feed yourself at the buffet. Remember your meals will be buffet style, so you could easily be spending 1-2 hours just chilling and eating.
There are boars on the island. I've only seen them once out of the 5 or so odd times I have been on the island, but they could be dangerous. Especially since the island is not lit after dark, it's probably best if you don't venture out too far and don't plan hikes after dark.
There are entertainment activities like a pool, and tennis courts... but I have never seen them being used, so don't bet on them being available.
In the summer, there is a camping area on the island. I don't have much to say about this issue, but according to this blogger, it seems to be owned by the hotel resort and you need to register with them. A quick scan of the google maps reviews tells me that there seems to be all the necessary facilities available to campers, and their Japanese website gives a good run down on things you can rent there.