My friend Andrew describes his house as 'dank'. It's always damp and things get mildewed really easily. If you have the same problem with excessive moisture, solve it for cheap at Aldi.
From Saturday 16 February, Power Force Moisture Absorber is at Aldi for $3.99 for a 354g tub. It's basically calcium chloride crystals, and they reckon it lasts up to 75 days.
Put a tub under the sink, in bathrooms, basements and garages, on bookshelves, in wardrobes and linen cupboards, and anywhere else that needs to be dry and free of mould and mildew.
This stuff might also come in handy if you drop your phone or other small electronic device in water. The usual advice is to seal it in a bag with dry rice, but these crystals might work too.