You do not need a qualification to set up as a Real estate agent in ireland. Just set up shop and away you go......
To become a member of IAVI, I believe you now need to have completed a course in Auctioneering or surveying. They will give you details on their website. I asked about this some years ago and they would accept course in auctioneering run by some of the institute of Technologies around Ireland.
I personally believe that all auctioneers should need some form of licence to operate. Somewhat like they way the states operates. This would allow the licence to be revoked if the Auctioneer commits any grossly wrong acts.
To be an auctioneer, you need to get a licence. To get a licence you need to have an insurance bond lodged in the High Court, apply to the district court for a certificate of qualification ( your intended application must be published in a local newspaper and can be objected to ) and then apply for the licence to the revenue commissioners- and then you need to reapply every year.