Peter (and Eva and sons) were wonderful! It's a bit tricky getting to the castle, but once we entered his address / coordinates, the castle was easy to find! Might be best the first time you're driving there to try and arrive before dark.
The castle itself was enormous and wonderful. You get a living area, large bedroom, kitchen, and the turrets for your own private use. The living area has a wood stove that's very warm (but ask Peter to light it for you!), and 2 hammocks that are so comfortable. I wasn't expecting them in a castle (I mean, who would?) but they were a great surprise. Almost as great of a surprise as the bathtub!
I wish we had stayed longer than just 2 nights - the castle felt more like a home than just a room for rent. Next time we're in Ireland we're definitely going to try and come back!