I've been renting out my original ppr for 5 years and only this year have had to pay €200. If you had been registered with the PRTB you could've offset 75% of the mortgage interest against any rental income received. You're allowed to offset expenses such as insurance, life insurance, capital allowance etc . That along with the 75% of mort interest might well have meant you'd owe little or nothing but no point saying that now.... If you lived in the house for periods during each year then you might fall under the rent a room scheme which allows you to earn up to €10,000 before any liability but you'd still have had to do returns . Hope it works out for you