Price for basic accommodation in Santa Teresa, Costa Rica?

Me and my girlfriend are planning on staying 1-3 months in Santa Teresa, starting in May. Does anybody know how much we can expect to pay in rent, and if there are any good places online to look for apartments? Or is it better to look for a place once we’re there? So far we’ve mostly found more upscale options online but we just need a place that is safe, clean and that has a kitchen. A small studio would be fine.
Any help with this would be appreciated!