I'm not certain, but i think the original plan for the RPA was free parking. However, a year before they opened they were getting phonecalls asking them when people who working Sandyford Industrial Estate could use their car parks there. So minds were changed.
€8 a week in a train station certainly beats the proposed €130.50 per week (assuming 5 days x 9 hours x €2.90 per hour) in Dublin City Centre - thats €6,003 over a 46 week year.
http://www.dublincity.ie/RoadsandTra...t)ByeLaws.aspx