Contracting, ltd company , pension mortgage

Hi - I may be entering the world of contracting in Ireland in a short time. I was looking for opinions on setting up as a limited company and contributing to a pension. Is it possible to get a 'pension mortgage' or something in this way ? Can you do that as a sole trader or alternatively by using a ltd company? Any idea of the advantages, disadvantages? Could you move money from an old scheme into a new one that is part of the company ?
Kindof rambling a bit , but thinking out loud and trying to figure this out .. Any accountants or others have experience of anything along these lines?