Hi Barbarossa
That is a bit difficult to follow.
Are you saying that in the other country, the interest rates are lower? So you can borrow on the security of your investment there and thus repay the mortgage in Ireland?
Is the other country in the eurozone? If so, it's a valid transaction. But if you are borrowing in another currency then you are taking on currency risk and it's not a good idea.
So your question is "Should I borrow for 5 years or 10 years in another country?". It would be best to get advice on this in the other country.
But the AIB 5 year rate is 2.45% so why would you borrow at 2.99% outside Ireland?
The AIB 10 year rate is 3.2%, so again cheaper than in the other country.
So your decision, if I understand your question correctly, should be "Should I borrow for 5 years at 2.45% or 10 years at 3.2%?"
No one knows for sure, but I think that 5 years is better.
Brendan