This strictly a silent vipassana meditation retreat and it's very good. But there is no yoga involved. In fact they ask that you abstain from other practices while doing the 10 days.
The staff is friendly and all volunteer run. So they don't have a set fee. At the end they give you an envelope where you can give whatever you want.
I have heard that the retreats offered at Esalen http://www.esalen.org/page/sleeping-bag-accommodation are pretty good and start at $405 for a weekend course and $555 for a bunk bed, which for me is still too expensive
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Offers a wide Number of relitevly well priced retreates on a full Blown private Farm and Ashram. It is located in Grass Valley California. thats the best one i could find but i bet there are some secret gems out there