I lived briefly in Rockfield while my house was being redone. They were new at the time. Wasn't impressed at the time with either the quality of the build or the quality of the mangement company (conveniently located in Malahide!)
I agree Dundrum is a great area but I am guessing this price is for a two bed? Its still ridiculous for even a two bed why not offer way way less than the asking price its a buyers market.
Sometimes I think people in this country are so worried about offending sellers they will pay way above what a place is worth!
Try 20 - 25% less between E270,000 - E288,000, its more than I would like to pay for a 2 bed apartment with a likely rent of E1,400 - E1,600 p/month, your mortgage repayments would be 1,600 - 1,700 p/month + insurance etc., also the rental market is in decline due to over supply so the rental incomes may drop.
There are so many apartments for sale in Dundrum they are bound to collapse in price over the next year so hold tight until there are significant reductions. I lived in Dundrum and moved out about a year ago because of the massive amounts of apartments and the likely traffic problems if they are all sold (which didn't happen)