I found this hotel to be absolutely perfect. The room we were given was beyond expectations. It was very large with two beds on one side and Japanese tatami, low table and zabutons on the other. The view of Lake Toya from our room was fabulous! The lobby was beautiful and nicely decorated. The staff were very friendly. The buffet style breakfasts and dinner was delicious with such a huge variety of mostly Japanese cuisine. Very conveniently located within walking distance to ferry boat ride to islands and a short bus ride to Mount Usu. The hot baths were wonderful, with phenomenal view of Lake Toya while sitting in hot, wooden tubs outside under the stars. It was magic!
The only thing that I can say negative about this hotel was that the bathroom in our room smelled of cigarettes, probably coming from ventilation system. But since we took all our baths in the hot springs, it was not too much of an inconvenience.

Good: Fast email response, one of the open air onsens is fantastic, nice view from room, convenience store is nearby.

Drawback: No vegetarian dinner, no free bus service from JR Toya

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Room stayed: Jap style room with view of Mt Yotei and Lake Toya

Hotel is in front of the lake. Fantastic view from the hotel lobby. Wi-Fi provided at the lobby, so you can surf internet and enjoy the view at the same time.

Front desk staffs are very friendly. One of them can speak English quite well. They have quick response to enquiry email. I am so concern on this because not all hotels I booked in Hokkaido during this trip had replied my email, even though the hotel is grand.

One of the open air onsens has fantastic view. I was lucky to 1st experience the open air onsen when it was snowing, cool!

Room is big (especially I stayed alone). it has good view of Mt Yotei and lake.

Hotel doesn't provide vegetarian menu, so the room rate I paid is considered slightly higher (6500yen including onsen tax, without any meal). Anyway I feel still worth it.

Too bad that no free bus from JR Toya is provided. Although they provide bus from Sapporo, not practical for me to go back Sapporo from Noboribetsu just to take the free bus.

You may take Donan bus in front of JR Toya to Lake Toya bus terminal (320yen). Quite a far distance to walk to this hotel from the bus terminal though. But take it as opportunity to explore the area.

I did take the bus from hotel to Sapporo. It passed by Niseko and Jyozankei. Enjoyable journey because of the nice scenery after snowing.

Never try but you may ask the hotel staff if they allow you to alight at Jyozankei Onsen bus station. Since they response to email, drop them message so that you can make neccessary planning to save cost and time on transportation.

Bring along a book and walk around the lake, do some reading, enjoy the sculptures and serenity. We also took the 50 min. boat tour ( Yen 1320) across the lake. That was what we did for this one day trip to Lake Toya (not a big volcano fan. Otherwise, should take the robeway to see Mr Usu).
We followed the instructions on the website and booked their free bus service ( 2.5 hr ride). There is one 15-min stop over for you to use the bathroom , buy some drinks etc. The staff at the special counter at the bus station don’t speak English. But hey, you are in Japan. You know they need to finish their Japanese scripts and greetings. So do let them finish it. They will then give you a paper number tag, showing which bus you will take and which seat you are assigned to. They will then ask you to queue up starting 130pm and they will bring you to the right bus stop. Just follow the crowd.
I never like big resort hotels. But since we want to find a hotel with an excellent lake side view, we chose Kohantei. Everything is what I had expected – excellent view from your room ( of course you need to book a lake side room). In case you are on a budget and book a room with no view, you can still enjoy the view from the lobby. You can walk to the lake promenade directly from the hotel lobby. Their daily summer fireworks ends at end of Sept. At night, everyone wore their yukata and slippers , and enjoy the fireworks at the promenade.
We chose the dinner to be served in our room. Compared with the set dinner at other Japanese resort hotel/ryokan, I must say that the dinner is only so-so. Breakfast is buffet style ( In Japanese, they refer buffet as “biking”, from the word Viking) Again, breakfast is so so.
I do enjoy the serenity at Lake Toya but not really the hotel. If you seldom have the opportunity to use outdoor onsen/onsen in a very natural environment, you will enjoy their public bath on the top floor.

It cost us Yen 13000/night dinner and breakfast inclusive. Similar to many Japanese ryokans , there is no CCN/BBC channel. Wi-fi in the lobby.
From Lake Toya, we went to Josankei by Donan bus ( ~ around 2 hrs) . If you want to know how, do drop me a line.