Does anyone on the site have experience

Does anyone on the site have experience of renting out property long term rather than for holiday lets and if so what snags have they come across? As I understand it a normal rental period is four years but it can be difficult to get rid of a non paying tenant esoecially if they have a child, are elderly or have an illness. Any feedback would ne greatly appreciated. I live in Italy and am looking to invest some money in property. (I like to be able to see where my money is!!)