You may want to consider Yuma, Arizona. Yuma is located in the far south of Arizona. It is near Mexico. Yuma is set up for "snowbirds", people who live in Arizona in the winter and move north in the summer. There are many mobile home parks that cater to senior citizens. Since there are so many seniors living in Yuma there are a number of activities for seniors in the area. it is a short drive to Mexico where one can buy most medicines at a low cost compared to prices in the US. Los Algodones is the nearest town in Mexico - about seven miles west of Yuma. The biggest businesses in Los Algodones are drug stores and doctors. it is also one of the easiest Mexican towns to enter and leave from. You park your car on the US side and walk a couple of blocks to the town in Mexico.

I know people who live in the south in the winter and move to the Yellowstone Park area in the summer. These people work in the park during the summer. The pay is not high but you can enjoy the park and the surrounding area while being paid. If you like this concept you may also consider many of the smaller towns in Wyoming - low cost of living, low crime rates, good fishing, etc.