Stationcourt in D15 (Coolmine, off the Clonsilla Road) is a really nice development, well looked after and doesn't seem to have many issues. There are 1,2,3 bed apartments and duplexes there and you should find something close to your budget. It's not as close as Waterville to Ballycoolin but would be a better bet. There are some rented apartments there but a lot of owner occupiers as well. It's also very close to Coolmine train station, walsking distance to Blanchardstown shopping centre and has a new creche on site.