I'd also recommend staying in San Jose and taking day trips to Manuel Antonio National Park, La Paz Waterfalls,
Poas Volcano hike, the pre-Columbian Gold museum and children's museum, and butterfly garden.
Very inexpensive to fly round trip from SLC, Denver or Las Vegas. Accomodations are inexpensive and so is food. They also take U.S. dollars and will give their currency as change at the going rate. Many residents speak English too.