We had a lovely stay with Danielle and François. Their apartment is in the Portobello area just off of a main street lined with restaurants and shops, but is still quiet and residential. It's also right next to Iveagh Gardens, an incredible park that feels miles away from the city. You're pretty much at the south end of anything you'd want to see, but it's just a 20- to 30-minute walk north or northeast to "tourist" Dublin (Trinity College, Temple Bar, Museum of Archeology) and a little further to anywhere north of the River Liffey. We ended up spending most of our time south of the river, which was plenty to occupy us for three days.
Danielle was flexible about arrival time and was able to meet us in the morning. She had also given us excellent directions for arrival options from the airport. (We took Aircoach to St. Stephen's Green, and then walked about 15 minutes.) Danielle and François were full of recommendations and provided a few guidebooks in the room. On Sunday, François made us delicious crepes. It was a fun stay in a fun city. Highly recommended!