I'm living in Ashbourne and have heard both good and bad opinions of Killegland. I believe there are un-rented units in there.
There are other areas of Ashbourne that would provide a much more reliable rental income. Where I live, whenever anything comes up for rent, it's normally gone within a week or 2.
I have some friends living in Kilegland and they love the place. Great location. The only thing is to check out the windows. They all have trouble with the wooden windows having a bad draught and some have mould.