Trip to Ireland - is this too ambitious?

Yes, I think so. I'd suggest choosing the North or the South, and do that. Do the other next trip. You'd have an expense returning the car in the Republic. It's very time consuming to move every day to a new lodging. Are you able to see a logical base location or two? With a car, that would be my plan, so I'm moving every 2-3 days instead of EVERY day.

There is no good Train connection between Dingle and Dublin. Dingle would be the wrong place to return a car.

How about taking the bus from Downtown Dublin to the airport. Rent your car there and go on to Belfast. Don’t double back to Belfast but spend the night on Antrim Coast. Return you car at Dublin airport at the end of your trip.

Thank you for your answers. Thought it was too much.

I think from Dublin, take train to Belfast, stay overnight, then back to Dublin. Rent car at airport and drive south and around to west coast seeing Cliffs of Moher, Adare, Dingle, then fly out of Shannon Airport.

Go raibh maith agat - Thank you!

I would suggest taking Belfast off of your list for this trip. To take the train to Belfast and then try to get up to the Giant's Causeway and back, plus see the Titanic museum probably isn't doable. To go all the way to Belfast just to see the city and the museum probably isn't the best use of your time when you have so few days to work with. Having that extra day to work with on the rest of your route will make a big difference as there is a lot to see, and you will want to stop and linger a while along the way.

Staying at a different hotel each night will exhaust you and waste a lot of time.

Arrive in Dublin in AM. Have you slept on the plane? Are you jet lagged? I'm pretty good at sleeping en route but I've found it's better to plan day one as a jet lag day. Get fresh air and sun, walk around. Expect not to remember much and be out on your feet if you do anything low key or indoors. I remember taking a canal cruise on day one in Amsterdam with my family. No one slept well on the flight and the whole group was out like a light. It was a complete waste of time and money.

How many sights do you want to see in Dublin? Your itinerary is fine if you just want to walk around and look. If you want to visit any sights, you need more time. If you can sleep and only want to see the city, a hop on hop off bus may work.

I would probably rent the car outside Dublin and drive to Belfast so you aren't renting in one country and dropping in another. On a quick trip, you won't have time to work with bus schedules. Trains don't really cover Ireland well, so keep the car all the way and return it back in Dublin. You could also plan a bus from Dingle to Dublin (and return your car there) but that depends largely on the bus schedule and whether they will hit you with a drop charge (seems to be more common, even in one country, these days).