House Cleaner - Full-time / Part-time

This would be a monthly (or more preferred every other monthly) cleaning of an unused upstairs. 2 bedrooms, an unused bathroom (so really only keeping up with water marks in toilet) and a family room. I would cover beds and cloth furniture in plastic, so those wouldn't need dusting or changing. I would just need dusting, vacuuming, knocking down cobwebs and dusting/sweeping of stairs. I may add downstairs foyer (also part of the unused area)