Used cars in Zihua and/or Mexico

Apparently the dealerships here in Zihua do not regularly carry used cars. If you happen to just time it right, great. If you want to make your purchase at a specific time, and have a specific make/mode/year in mind, as we did, this is very unlikely to be successful. We bought our in Mexico City and are very happy with it. We learned that, for example, Nissan will have 2 or 3 locations where they stock all the used cars for the dealerships. Similar with other brands. Buying from the dealership was very easy-no hassles at all.