Sounds exactly like how I travel. I'll go without hot showers, walk, sleep on the ground, etc. But spend the money when it matters the most.
What inspired the question was all the posts on the Bolivia forum about booking tours. Not so many about doing it on your own, etc. Lots of costs in the several hundred US dollar range. Was making me nervous.
I don't have to go all "shoe-string" with it, but I just came off another long trip via motorcycle that cost me more than I thought it would, and then I booked this Bolivian trip without much time to recover the old wallet health. ;)
Just didn't want to get there and discover that I can't see any of the awesome stuff I've seen photographs of, without having to buy several hundred US dollar tours to do it. I don't have any problem haggling, staying in dodgy accommodations, eating street food, etc. in order to save enough budget for tour transport every now and then.
Judging by my research on a similar trip so far, I think you'll do fine with that mentality in Bolivia. Figure out which inaccessible places are high on your wishlist and save money for these tours. Take public buses, stay in cheap hostels (or even camp if you are bringing a tent), etc. exactly as you planned. Other than the tours, Bolivia is one of the cheapest countries in S.A, and even the tours seem affordable in comparison to surrounding countries.
