First, I am the owner of the Pucon Kayak Hostel
and an international high school for kayakers. I say this not for creditability I just want you to be aware.
I see year after year two groups planning 2-3 month long trips. A. Is the elaborate multi-country trip, and B. is the base camp program.
The question becomes, "do I see more and get more passport stamps or stay in one spot and likely get bored?" Although, this question might be naive.
Perfect example is when my friend Logan from WV showed up after two months of a multi-country trip with his girlfriend. You might think traveling in South America with a hot 24 year old is as good as it gets. Logan had no vehicle, was stretched thin on money, and tired. He was happy to stay put in one place for as long as I allowed him a free place to stay in Pucon. It seemed him and his girl were happy to have a warm private bed too. Logan's problem was that the costs and demands of his elaborate trip wore him down. He couldn't even afford a shuttle to a local waterfall run so I was taking time out of my work day just to help him paddle the Upper Palguin. That's the kind of guy I am... always looking for an excuse to go paddle is the point. But really he was stuck at whatever hostel lodging he found and the things offered within walking distance.
Demshitz- they come to Chile year after year. Why? Because the rivers are fantastic and there is plenty of exploration opportunities to fulfill that whole, "I want to do and see more... concept" The Dempoops know the local runs and fire them up like no others. But what's even cooler is they research the maps and plan first descents (and there are still a ton) to get their exploration bug. They paddle everyday and are always off on a new mission. They have economical apartments and buy vehicles. Apartments and vehicles have tremendous advantages in other areas too.
It's not just the Demshitz. This year Kurt Casey a class IV boater knotched 4 first descents in 6 days. Kurt started the Chilean guide online guide book. It's a great resource... RiversofChile.com
The price you'll spend on your vehicle that may or may not make it to Chile will be more than buying one in Chile. FYI- gas in Chile is approaching $us6/gal. You're gas will cost as much as a cheap vehicle.
It's sweet to come home to your own space. I see it year after year the guys doing the 2-3 month multi-country trips burn out, run into financial issues, break down, and go home early.
The only guys who make it through the entire season are the guys with some stability of bed, vehicle and equipment.
My advice is to choose a couple of great destinations to base camp out of. Places with great great whitewater that allow you to be happy in that whitewater community and also to take your exploratory missions too.
Costa Rica has Turrialba, Ecuador has Tena, Chile has Pucon and the Futa, Mexico (I've never been so I can't say).
And if you make it to Pucon then look me up I'll show you the local runs and buy you a beer.
Pucon Kayak Hostel