I wonder, though, if you really are? Even the American “poor” can consider themselves lower middle – they have all the necessities of life, and lots of things that real poor people don’t have anywhere in the world.
An apartment in Mexico for $500 could be pretty good, or pretty bad. Here in the USA, you’ve got a damned good sense for “good” vs. “bad”; there are lots of subtle and not so subtle clues as to what’s good or bad, and you can decide your own comfort level on that, in the vast majority of cases. That’s not necessarily so in Mexico. There are, of course, the obvious enclaves with the casetas that don’t let the bad guys through (unless they’re armed and blast their way through, like in Hermosillo in Nov. 2005), but there are lots and lots of great neighborhoods that – as an American – don’t inspire me, but I’m assured by people that know are really great. Likewise, there are those that look appealing, but aren’t necessarily so. The cultural norms really, really are that different! I wouldn’t make a final decision without someone you really trust. On the other hand, I’ve never been to Quintana Roo, so can’t specifically say anything concrete.
I’d say that for $7.50 an hour, though, you’ll live a lot better than the people that only make $20 per day. The Mexican middle class is estimated to be 20%-30% of the population, and when you start to mix with the middle class, you realize very quickly that Mexico’s not a backward, third world country for them. On the other hand, I guestimate that I could take a 50% pay cut and live reasonably well in the Bajía region (central to the country), but that’s still well above $7.50 per hour. On the other hand, I’ve got an acquaintance that’s an illegal immigrant in Mexico (i.e., he’s a gringo) that gets by satisfactorily. He does “odd jobs” in the industrial sector, and before alcohol ruined him he was a pretty good manufacturing engineer. I doubt that he even averages as much as $7.50 an hour, but he get by, even with the occasional night in jail (like I said, booze).
I think English teaching is always everyone’s first idea, but it’s kind of a cut-throat, saturated market – again, in the industrialized areas that I’m intimately familiar with. Non-industrial areas may not have such a need. So… what’s your bachelors degree in? Maybe there are suitable, better-paying alternatives? And why Playa de Carmen specifically? Would you consider other areas?
Would you consider high concentrations of other Americans/Canadians? Perhaps you have a service you could offer them, especially being a native-speaker yourself?
Legally, what you’ll need is an FM3 visa, which has various amounts of time. You can naturalize in Mexico, too, and maintain dual citizenship. I think it lets you vote, but unlike here, you can’t run for office (my dreams of being governor of Guanajuato are crushed). Typically (like here) you need a job offer prior to being issued the visa, or if you’re going to open a business, you need a certain amount of assets. Unlike here, the penalties for illegal immigration are quite strict and often lead to jail time rather than simple deportation.
If you can manage it, it’s a great place to live economically, assuming you’re already somewhat made, or can earn more than the average salary. Great for retirees, and great for Americans working for Mexican locations of American companies, but (again, depending on how you like to live), maybe not up to our normal expectations for what the local economy considers an average salary.