Hi Lisa,
I just returned from a trip to Costa Rica, and not only did I visit Guanacaste and stay for a short time in Nosara (expensive), but I bought a house on the outskirts of La Fortuna. That area has a cooler and moister climate than Guanacaste, and as a result also spectacular rain forests, in addition to Arenal Volcano and associated hot springs, and Lake Arenal the largest lake in Costa Rica. I am closing on the house purchase in early October, and will be renting it out. Let me know if you might be interested in renting in that area. Since I don't own it yet but fully expect to within a couple of months, you'd be first in line to rent!
Pura Vida,
Mike