I know those tactics, that's what people do in EU as well, I mean EU citizens, living in another country. I think you are only allowed to stay for 3 months. It's doable when you live close to the border, but traveling hundreds of kilometers or flying can be tiring.
I know less about Costa Rica country and what I know is not exactly good. I know Costa Rica has no extradition agreement with my country and that's where the most honest politicians/fraudsters are going :)