We spent 3 weeks this summer at Casa Linda, and loved every minute of it. The house is brand new (built in 2015) and very nice looking and comfortable, and the views are amazing! The pool was really nice to have for a refreshing swim in the afternoon/evening...
We enjoyed the quietness of the area, and the fact that we were surrounded by birds and howler monkeys. The kids had lots of fun digging through the entire hillside around the house and looking for insects, lizards, iguanas, and all sort of other animals. Of course we also went to the beach almost every day, and did a lot of tourism as well.
The beach at Playa Grande is very nice, long stretches of white sand with good waves. The kids learnt to surf at the nearby surfing school (Playa Grande Surf Camp or something like that), and then we rented surf boards a few times and they did a lot of "learning by practice".
We went to Tamarindo a lot, for shopping, dining, etc. It's an easy 15-20 minute drive, or you can go across the little estuary if you're going during the day.
We got to visit a number of tourist sites. Costa Rica is not a very big country, and the house is close a lot of nice hiking areas, zip lining rides, etc. We went to Monteverde, Rincon de la Vieja, San Jose, and even Manuel Antonio. We also went on a 3 day tour of the Nicoya Peninsula (the owner recommended it to me), which was a lot of fun (and interesting driving!)
We really liked our stay in Costa Rica, and Casa Linda was the perfect place for us.