We stayed 3 nights at Mar Rey. The small hotel is in a perfect location to enjoy Tamarindo right in the main area and a few steps from the beach. It was very clean, and the staff was mostly friendly, nice pool. I only downgrade them to Good because of a couple glaring issues that are easily correctible:
1) they have NO pool towels, and some employees refused to exchange our wet (pool used) bath towel for a fresh one, expeciting us to reuse it for our shower later. Not acceptable for a nice hotel. Also towels were worn.
2) They don't provide any facial tissues or napkins in the room, only TP.
Other than this, it was a good stay and recommended. Be aware though that it is directly in "Downtown" and is noisy outside until midnight at the bars and shops. No fault of the property, just be aware.