Like a Skyscanner fare summary, but for a road trip and with considerably more denial. Per person, breakfast included.
Not included: petrol (it's ~1,100 miles of it), dinners and lunches, the Shannon ferry, attraction entries, and whatever happens in Crowley's. Marine Troon on Tuesday is a personal pre-trip cost and sits outside the shared total. The Dromoland heritage fee (€25/night) is on top.