When it comes to raising money for an overseas properties you have two options:
1) Release equity in an Irish property - i.e. use an Irish bank to get a remortgage.
2) Raise the money with a bank in the country where the property is located.
I have two properties overseas - both in Spain. The first was funded thru an equity release on a property here in Ireland. The second was funded with a mortage raised in Spain thru a local Spanish bank.
FYI the Spanish bank asked for very similiar documents to the banks here in Ireland - ie proof of income, proof of tax compliance, bank statements etc etc.
Hope this helps.