I booked the apartment (a basement flat) to stay with my family (consisting of two adults and one toddler). The communication with Barry went smoothly, he allowed us to check in a little earlier, and the flat was as described.
It is a basement flat in a city close to the sea/with a maritime climate. You should be aware that (as we learned what appears to be quite common in Ireland) the heating in the flat only works for prespecified times, as in Barry's description. He is willing to adapt the heating to the times you ask, but the walls and furniture cool out, making the place relatively cold even when the heating is turned back on.
If you travel in an adult-only group, this flat will give you (to my best knowledge) an excellent price-performance ratio. The flat lies in a quiet street with a brief walk to public transport. The city center is within absolute walking distance.