Nowadays there exist a lot of "squatter rights" laws, most of which being extensions and very loose interpretations of basic human rights' international laws. All communistic in nature... My premise is what one can do to protect ones own property, if you ever happen to have a squatting intruder problem. In certain countries such an issue is not so straightforwardly resolvable if one want's to do it by the book and "humanely". However there are other legal means of permanently getting rid of such parasites without actually breaking any laws.
Basically if the property is actually yous and you want to permanently evict a squatter, that has proved him/herself reluctant to oblige to reason and owner's right to property, do not ever forget that there are self-defence laws you can use to your favour. All one has to do if one has the aptitude and want to stand one's ground is straight up kill the intruder. Once you have proof of ownership of the place you can walk in, liquidate the pest and claim self-defence later. It's easer than one might think. Obviously it's not a solution that can be applied serially because it would rouse suspicions but it is definitely within the parameters of the law if executed properly and without second thoughts.