wow, after reviewing my post I left out a lot — it will be late june of this year, and there are two of us. traveling by rail from munich.

Odds are that hostels will not be that busy and you can book last minute, 3 days in advance is good.
Funny Farm is an old barn with acces to bar in Mattenhof hotel next door.
Swimming pool, volley ball sand court, Old ski tram with happy hour specials.
Beer tent with happy hour specials. Hit happy hour because it is expensive!
5 Swiss francs per beer in plastic cup. Happy hour is 2 for 1
Funnyfarm is back off the road so noise by beer tents are not a problem.
Firepit as well at night.
You can also get bunks inside hotel with ensuite bathroom.
Disco in basement of Mattenhof Hotel next door.
1/4 block from Balmer’s
Balmer’s is converted homes and business on main road.
Happy hour on beers and a small cafe.
Gift shop, laundry and a disco in the basement.
Also runs a giant circus tent a few blocks away.
Very strict security because neighbors complain of noise all the time.
Can’t stay outside and socialize at night.
Anyone can just walk in and join the fun.

Both places use different High Adventure sports companies.
I prefer Alpin Raft at the Funnyfarm. You get all the equipment and wetsuits on the spot.
At the beer tent at night, they show the videos of the people that went skydiving that day.

Within one block are cheap hotels, internet cafes, laundry, supermarket, bike, moped, electric car rentals, etc.

Once you check-in, you get a free bus card and can travel to lakes for swimming and to train station which is only a 15-20 minute level walk.
Watch your weather forecast and try to visit Interlaken between the rain storms for the best views. You may want to switch and do Interlaken before Munich for better weather.

If you go canyoning, choose the “Grimsel” trip. Water flow is controlled by a dam and less likely to be cancelled by rainfall.