What you are looking for is an execution only broker. There are plenty of these online and they usually charge between about €10 to €30 per transaction.
If you look around this site, there are plenty of threads discussing them.
Some of the bigger name stockbrokers like Goodbodys and Days tend to charge considerably more per transaction(1%+ I think). They justify the increased fees on the basis that their highly trained stockbrokers are also offering finacial advice.
You don't need this advice so stick with the execution only. Even if you did need finacial advice, I would go to an independant advisor whose fees are not based on the number of transactions you make