Well, as someone whose parents in law live on the Costa, and having been a visitor there myself many times, it's not a bad idea. There are a few Irish pubs-but theme only in The Torremolinos,Benelmadena Fuengerola area.Not much really live music-plenty of Karaeoke.Quite a few gigging musicians with keyboard, guitar, vocalist set ups, playing various more popular musics/hits etc but with the odd folkie/country tune thrown in. Good coffee/drinks and snacks(at least) and good music will pull in people,and the oldies soon spread the word, especially if they have good service and good prices.In the winter of course competition is high to get people in, but with prices being so cheap (summer/winter prices differ quite a bit) very many oldies don't even bother to make coffee at home after they've got up.There are plenty of oldies there through the spring/summer and autumn time as well, and whole populations of ex-pats who live there all year.They are not all wrinklies either, many are middle aged.

Folk music can include Flamenco guitar as well as USA/British/Northern europe styles. Irish stuff,especially the commoner music seems to go down well with the masses with specialist or more true folk having less appeal (except for all the people you know in your folk circles)But if the locals frequent and support you, then the wrinlies will as well.You'd have to be prepared for long hours, late nights and to suppliment income open during the day for drinks and snacks,maybe even breakfasts (about 11.00) but with the right marketing/flyers in the area and maybe open mike sessions with a guitar handy for those who haven't brought theirs with them, it could work.

Good luck-let me know when you are open and where you are.

Cheers