I think one rule is don't try to rent a property which is in a condition you would not live in yourself. So may landlords put rubbish and old furniture from there homes into rented property then wonder why it takes so long to rent. I think it's worth it to spend a little extra time and money on the furnishing because it last longer, looks better, rents quicker, an unrented property cost on average 400 euros a week. Recently purchased properties will rent at a loss so don't try to match the mortgage. If the property is nice it will rent. Also I think you would be better off renting it yourself and don't use an agent, use the service Daft provides.
I let a vacant property recently which I think was lovely after putting in on Daft I had 4 calls within 3 days. 3 viewings the 4 person had very poor English and could not find it. I priced it at the top end and all 3 wanted it and I had a tenant moved in within 3 weeks from start to finish.