Travel in Ireland
 

12-15 day trip. Three or Four base camp locations. We need transportation. Where would you stay for 4/5 days? We plan on taking day trips around each County.
Trying to avoid driving if at all possible.

Your question is impossible to answer.

How are you going to day trip "around each County" when there are more than 2 dozen counties in Ireland and you have a 12-15 day trip?

WHAT DO YOU WANT TO SEE?

What is your budget (nightly lodging costs)?

If you're not going to drive, how do you plan to get around? Buses are slow, trains don't go everywhere.

What are your flight arrangements? Into Dublin out of Shannon? Into and out of Shannon? Into Shannon out of Dublin?

What DO YOU want to see? Get a few guidebooks and determine what sights are important to you. When is this trip?

You want to see 26 counties from 3 bases? all 32 counties from 3 bases? not going to happen. You can go round the Island in 16 days following my plan as a road trip, tried to fit it into 14 but couldn't. Not so people would enjoy it.

If aiming to see the whole island in 15 days by public transport you have even less chance.

As said already you need to give more information to get a better answer but before someone comes on linking all sort of foreign sites for public transport try the Irish one
http://www.journeyplanner.transportf..._TRIP_REQUEST2