I stayed at OSA Mountain Village for 3 months in 2014 and it really is a little slice of heaven. Nestled into a jungle up on a mountain, the villas are spacious, modern, and are fully equipped with everything you need to have a relaxing stay.
We woke up to howler monkeys in the morning and watched toucans fly over head while watching the sunset every night. The staff at the resort are incredibly nice and will help you plan out whatever activities you are looking for.
OMV truly is a unique spot with it's gorgeous views, organic gardens, fruit trees, waterfalls, zip line canopy tours, butterfly garden, and there is even a volunteer center on the grounds where people come from all over the world to learn more about sustainability and organic gardening.
If you are planning a trip to Costa Rica, I highly recommend visiting OMV. It is definitely a place I will be visiting again and again.