That sounds like an excellent plan for a quick discovery trip! Fall really is a lovely time
to explore the island. :)
October is outside the main tourist season, but still in the so-called 'shoulder season'. This period usually sees fewer tourists coming over, while ample tourist businesses will still remain open. You'll find many accommodation providers throughout Ireland, so booking in advance won't be really necessary during this time. That being said, I'd recommend you to book your first night of accommodation none-the-less, just to be sure you can spend your first day stress-free. If you're planning to stay the night in Dublin on your first or last night here, I'd recommend booking regardless, as Dublin is a popular destination year-round. You can use our accommodation search tool
to browse through all reputed accommodation on the island.
Have you contacted a car rental company yet? And do you have an idea on which route you guys will be taking?