The first obstacle is air travel, always. You can occasionally get the bargain-basement price of about $800 to go to Europe -- IFF you go at exactly the right time of year and find the leprechaun selling that ticket out of his pot. More usually, airfare to Europe runs about $1200 -- and can go as high as $1500, even for the cheap seats. A Spring Break trip is thus less expensive than a summer trip, but you wind up visiting the Alps in shivering time.
All that being said, the trip gets built out from there. Next after airfare is getting to and from Kandersteg (and anywhere else you want to go). There's a great rail fare from any Swiss airport or border train station to Kandersteg for Scouts, if that's the only place you want to go. Swiss rail passes or Eurail passes are more expensive, but then you can go other places. Other than rail, there are buses and your own feet -- the one expensive, the other tired. I'm not interested in renting a car in der Schweiz.
Then, there's food and accomodation. Eating out can be expensive. Camping is cheaper than lodges or hostels, which are cheaper than hotels. And so on. I looked over Kandersteg's programme offerings and price lists. And here's what I finally came up with.
A weeklong, no-frills trip to Switzerland would mean flying into Geneva overnight, and on Day One taking the train to Kandersteg: check in, get campsite set up, etc. Start acclimatizing to the altitude. Day Two, we would be both weary and still getting used to the altitude, so it would be spent doing camp activities that Kandersteg supplies -- sort of like a layover day at a Philmont staffed camp. (They have ropes courses, rock climbing and rappelling, etc.) Day Three -- still acclimatizing -- we could go into town, either by bus or on foot. Maybe even go to nearby towns. The Thünersee is only a few miles downhill, and Interlaken is supposed to be a cool place. Take a packed lunch, eat dinner out, play tourist and shop for souvenirs. Then on Days Four and Five, take one of the overnight hikes to a mountain hut -- a kind of mini-backpacking trek through the Alps. Day Six, check out, take the train back to Geneva, crash in the airport overnight. Day Seven, fly home.
This basic trip could be done over Spring Break, though we normally plan for summer trips. It would cost, at a SWAG, somewhere between $1600 and $2100 apiece, depending on lots of factors (like time of year). This makes it comparable in price and duration to, say, a Sea Base excursion or a return trip to Great Britain. Very doable.
Now, if the Venturers wanted to make it, say, a nine-day trip, we could add an extra day doing stuff at Kandersteg, or an extra day touring about by bus, or do a three-day schlep through the Alps. Mix and match as desired. Additional costs would be minimal; once you've swallowed the basic cost of getting there and getting around, you've got the biggest obstacle conquered.
So, I'll pitch this to the Crew, with this caveat: The challenge of this trip is not just raising the dough; without a real commitment to forming the crew and preparing to do this kind of trip -- meaning, attendance and participation over the next year -- it's not worth even sharpening the pencil to go beyond this vague summary.