I live in Nosara Costa Rica, with my wife and daughter. I have properties here, and also am the Broker/Owner at RE/MAX First Choice Realty in Nosara.
Stayed here for 10 days with two friends who surf and it worked out well for our trip to Nosara.
It's a different kind of place than other airbnb places I've stayed, which have all been people's homes. This one is more of a brand new retail condo space with sparse decoration & hotel style beds and towels. The king or queen sized bed was really comfortable and the place was very clean, as you'd expect from the general aesthetic.
The location is about a 15m walk to the beach, so you need to learn the nameless dirt roads of Playa Guiones to get around the small town, but once you figure it out, walking the roads becomes a relaxing ritual.
The air conditioning was strong and saved us on hot nights, and there's a TV you can use to watch Spanish language versions of Will Ferrell movies when you're burned out from the beach.
Only real issues were small: weak water pressure in the master bedroom shower, non-working dishwasher (not a big deal), and a strong smell of cleaning supplies that took a few days to wear off when we first got there. We mentioned those things to the property manager Tiffany, who was nice and helped us out a lot on our trip.
Jeff was really helpful too, even took us home our first night when we couldn't figure out the dirt roads in the dark. (If you're going to Nosara for the first time, pick up a town map and bring a flash light.) He's an easygoing American guy who's been living there for a while, knows the area well and is always around if you need him.