Couple of things to consider:
* Most tours (whether from Chaa Creek or elsewhere) are predicated on a minimum number of people, usually four. So a US$200 tour costs that amount whether it's for one, two, three or four people. Beyond four, it might be US$50 a person. Usually, at least in high season, it's no problem meeting the minimum. Operators often switch off and combine groups if they don't have enough people going with them.
* Chaa Creek is among the most expensive tour operators. They cater to a more-affluent guest, not to the budget traveler. But they offer a quality product and stand behind it. The tour guides who work out of Eva's or one of the budget hotels will be much cheaper. For example, you can get a trip to the Pine Ridge for US$25 per person. Most are fine, but check around with others who have taken the trips before committing.
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