1. Most renegotian are to bring treaties in line with OECD models if not already so.
2. If you spend 183 days in any tax year or 280 in any two consecutive tax years you remain Irish tax resident. If you leave Ireland to reside permanently abroad, you could be considered non-resident from the date you leave under split year rules. You will be treated as not ordinarily resident from the commencement of the 4th tax year, if you have been non-resident for each of the preceeding 3 years.
3. As a non-resident landlord, your tenant is obliged to deduct basic rate tax from the gross rent and pay this over to the Revenue unless you appoint an agent to act on your behalf with the Revenue. From 2009, you only get tax relief for 75% of your mortgage interst payments against your rental income. You will only get relief for mortgage interest if you are registered with the PRTB. You can generally claim tax relief for any expenses related to the letting of the property (e.g. repairs, redecoration, insurance etc.) after the date of the initial letting. Getting the property into a state in order to let it out would not be allowable. Capital allowances may be granted if the property is let furnished.
3.You will be taxable on your taxable profit - rental income less tax deductable expenses. If a loss you can carry this forward to future years. If a taxable profit - tax at usual rates. Personal tax credits for non-residents calculated at a proportion of tax credits x Irish taxable income / Total worldwide income. If in Canada, they will give you tax credit for Irish tax paid (may be subject to restrictions) against Canadian tax liability. Check this out with Canadian tax advisor.
4.CGT calculated on taxable gain - if no gain no liability to CGT.
5. If you have Irish arising income, liable to Irish tax. Depending on treaty may be able to reclaim tax credits. Need to look at treaty to confirm.
Above are general guidelines. I would suggest you get professional advice due to complexity of your situation.
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