We crashed here for one night. The girl who runs the property is lovely and called me before we arrived to confirm details and helped us get a transfer from port.
The rooms are adequate, and they serve a nice breakfast in the terrace (toast with jam and honey, hard boiled egg, breakfast cakes, and choice of coffee or tea. The juice is a mixed powder and is pretty awful).
Main complaint are the really hard beds and the water in sink and shower is salty. So you brush your teeth with salty water....otherwise it’s totally fine and is probably one of the cheapest places to stay near Oia (bus stop to Oia right in front, but in order to come back you would have to go to Fira and take another bus from there).
If you stay here to save a few bucks, you can cook in the kitchen, but you might want to rent a car to be able to get around the island easily. Honestly, you are better off staying in the less touristy villages like Megalochori which have more affordable options that are nicer.