I second Montezuma! I had heard it was amazing and that I would fall in love with it. I took a ferry from Jaco as well and pulled up on the beach and was underwhelmed at what I saw. I got a room at a hostel and decided I would only stay a day or two because I couldn't really imagine what there was that would be so amazing about the place. Fast forward almost two weeks and I still hadn't left. It is the kind of place that sucks you in and makes you feel at home. I met locals and travelers alike and made friends that I still keep in touch with to this day. It is also easy to get a bus and head to other beautiful places like Santa Teresa, Mal Pais, and other small Nicoya peninsula towns.
FWIW my parents actually retired early to Costa Rica. I am there quite often and have been to most parts of the country. They also have quite a few hook ups of local friends that are guides, taxi drivers, business owners, etc. in the area and local phone numbers, so if you guys need anything you can shoot me a message and they could probably have ideas for you for any budget. I am almost 30 and love going cheap in hostels and surf towns, but they are closer to 50 with money to spend, and have visited every nice resort and spa from north to south.