Living in Adelaide South Australia we have a fairly dry climate, winters are cool and damp, and summer is hot and dry. Humidity is rarely a problem Although with the last few years of global warming or climate change, whatever you prefer to call it, the humidity levels have begun to rise. We normally use evaporative coolers for air con in summer, I think you guys in the states call them swampys. As I understand it, it's not the humidity per se, but the dew point.
If the metal surface temperature, or any surface, drops below the dew point then you will get condensation. Dehumidifiers will certainly help control the problem, but a decent reverse cycle air con will also work, some even have a dehumidify setting. A dehumidifier is really only an air con with a slightly different setting.
The problem is that after cooling the air to get the moisture out, it is often too cold so you need to reheat it for comfort this can be arrange by running the air over the condenser coils, so there is no extra power required for the reheating.
Large commercial units are often set up that way especially in humid climates.