During that six months our Mexican and US attorneys were working to secure a permanent work visa called a ‘FM3′. It was in addition to my US passport that I had to show each time I entered and left the country. Barbara’s was the same, except hers did not permit her to work.To apply for the FM3, I needed to submit the following notarized originals (not copies): 1. Birth certificate for Barbara and I.
2. Marriage certificate.
3. High school transcripts and proof of graduation.
4. College transcripts for every college I attended and proof of graduation.
5. Two letters of recommendation from supervisors I had worked for at least one year.
6. A letter from the St. Louis Chief of Police indicating that I had no arrest record in the U.S. and no outstanding warrants and, was ‘a citizen in good standing’.
Finally, I had to write a letter about myself that clearly stated why there was no Mexican citizen with my skills and why my skills were important to Mexico. We called it our ‘I am the greatest person on Earth letter. It was fun to write.

Source: An American working in Mexico… – Nobody Asked Me…

And this is not the exception but the rule in countries south of the border but they won’t tell you this. And as immigrant, you will not even come close to have the same rights that a national would like owning real state. In fact, it is not unusual in this day and age that cops and the military can kill illegal immigrants without having to observe any consequences.