We stayed at Casa Verde recently and we had overall a great time at Cahuita. The house is located on a perpendicular road across the road that goes to the beach. You cannot see the beach from it, but you can hear the ocean, and it is about 1 minute walk from Playa Negra. The condition of the house is very good and clean. But it does not have some of the essentials for cooking that you can find in other places (oil, sugar, coffee, spices, paper towels/napkins…) so be prepared to bring them if you plan on cooking. Also, the bathroom upstairs could use more hardware to hang the towels, there is only one towel rack and is not enough for two people to hang towels so they can dry, which is quite a task with the ambient humidity, plus, bring your own shower gel, because there was none. And, if you plan on going to the beach, bring your own beach towels. The bedroom upstairs is the coolest (temperature-wise) to sleep in but the bed is not firm, the mattress in the downstairs bedroom is firmer, so you can choose what you like.
You can just spend the day sitting on the patio and enjoying nature, it is sooo relaxing! You can see the parrots in the morning, hear and see the monkeys jumping in the trees, listen to the ocean in the background and just chill with the house cat, Guinness, who is very, very friendly.
The owner, Annie, is very responsive and attentive, she can help not just with the house accommodation but also with transportation and questions about local things to do!