In my humid climate, I run a dehumidifier most of the time. It sits in the kitchen sink, drains into the gray tank. Since I park on gravel, I leave the valve open so it can drip on the ground.
One thing to be aware of when selecting a dehumidifier. The old mechanical control types would restart after a power failure. Some of the electronic models will not restart automatically after a power failure, requiring you to restart the unit. There are electronic control models that store the settings and restart automatically when the power is restored.
Without the automatic restart feature, you could leave your rv and have the dehumidifier fail due to a power failure.
Fred