My current basement is about 60-65% with no help. The basement I'm moving to is about 80%, so I put two dehumidifiers down there.
A big 120 pint on the north side which is below grade, and a 70 pint on the south which is where it is a walk-out basement. These are modern units, and have a "basement" setting. That setting calls for 50% humidity levels. The below grade unit runs a lot. The walkout unit runs sparingly. The basement is drywalled and there is no mold on the drywall or floor moldings. After I set up the dehumidifiers, it does smell fresher down there.
