Lowest I'm seeing in Blanchardstown for a room is €160 (the lower amounts are twin shares)

Lowest I'm seeing in all of Dublin is €140 once you exclude twin rooms, monday-to-friday terms and whatever "Dublin Host Families" is

I have sneaking suspicion those are per week prices

yep sorry I meant the polar opposite of how that post read! There's hardly anything remotely near Dublin that's in the sub 600 range was my point.