Whatever locational disadvantages your startup has, they are (I think) more than made up for by the fact that you're working from a location with very low costs of living and a very undeveloped frontier market.

Now, Im not sure if you're building your startup for the U.S/developed market or for the Latin American market, but I'd say there are a lot of opportunities for you if you play to the latter instead.

I live and work from Mexico, just north of you and I can see all sorts of extraordinary opportunities for those of us who have a more expansive knowledge of services and product concepts combined with our familiarity with the language, culture and economic landscape of our newly adopted home in Latin America.

You can work on this angle and really create something for your region from your region, instead of working at a disadvantage by trying to reach the more established U.S market needs from a place where you arguably have access to less resources than someone in Silicon Valley does.