We had our house pressure washed today, and the worker used a chemical to remove the oxidation on our vinyl shutters. Does anyone have a suggestion on a method to treat the shutters so that the oxidation does not continue to form? Some suggestions I've heard are to remove the shutters from the house (difficult in that my husband nor I am able to climb an 18-foot ladder!), wash them, dry them, and treat them with either boat wax or Armor-all. Any other suggestions that would use a spray mechanism?