What about retirement in cuernavaca?

Cuernavaca is a beautiful city. It has clear air and semi-tropical temperatures. It's about an hour's drive to Mexico City. It doesn't have as many gringos as Lake Chapala or San Miguel de Allende, but it is kinda on the expensive side, like those towns. And prices go up in any place that the gringos desire.
Check out the Choose Mexico book for more info.
And you can get more info at the clickoncuernavaca site below,

I was born in Cuernavaca, beautiful place. Climate is great all year around. My family and I are going there this Christmas. You are hours from great beaches and one of the biggest cities of the world. My husband and bother in law loved it the first time they went down for vacation. Now they can't wait for vacation time each year. House down there are in really good prices or you might consider building your own its a lot cheaper and you can design your home to your taste. That's what my parents did and now we have a beautiful vacation home to go to.