When I was there, I was on a bicycle. I took the bus to Tubercurry and cycled the entire Peninsula. As I recall, it was 2 days to Dingletown and a long day back. I was loaded for camping and although the hills are steep if you are crossing the spine of the peninsula, trips along the seashore are very easy. I would say that if you took the bus to Dingletown and stayed in the hostel the first night, you cold plan your BB stays for the rest of the trip the next day. You can easily get to the BB’s by rented bike or bus. The buses gladly put your bike whole and unboxed in the stowage below (unlike in the USA).